diff --git a/Backend/Application/Interfaces/IFileRepository.py b/Backend/Application/Interfaces/IFileRepository.py
index 9e7785a..908af32 100644
--- a/Backend/Application/Interfaces/IFileRepository.py
+++ b/Backend/Application/Interfaces/IFileRepository.py
@@ -23,3 +23,11 @@ def get_all(self) -> list[File]:
     @abstractmethod
     def update_status(self, file_id: str, status: FileStatus) -> None:
         pass
+
+    @abstractmethod
+    def update_folder(self, file_id: str, folder_id: str | None) -> None:
+        pass
+
+    @abstractmethod
+    def get_by_folder_id(self, folder_id: str) -> list[File]:
+        pass
diff --git a/Backend/Application/Interfaces/IFolderRepository.py b/Backend/Application/Interfaces/IFolderRepository.py
new file mode 100644
index 0000000..d13cefe
--- /dev/null
+++ b/Backend/Application/Interfaces/IFolderRepository.py
@@ -0,0 +1,29 @@
+"""文件夹仓储抽象接口，定义文件夹的持久化操作契约。"""
+from abc import ABC, abstractmethod
+from Backend.Domain.Entities.folder import Folder
+
+
+class IFolderRepository(ABC):
+    @abstractmethod
+    def save(self, folder: Folder) -> None:
+        pass
+
+    @abstractmethod
+    def get_by_id(self, folder_id: str) -> Folder | None:
+        pass
+
+    @abstractmethod
+    def get_by_name(self, name: str) -> Folder | None:
+        pass
+
+    @abstractmethod
+    def get_all(self) -> list[Folder]:
+        pass
+
+    @abstractmethod
+    def update_name(self, folder_id: str, new_name: str) -> None:
+        pass
+
+    @abstractmethod
+    def delete(self, folder_id: str) -> None:
+        pass
diff --git a/Backend/Application/Skills/FaultTreeSkill.py b/Backend/Application/Skills/FaultTreeSkill.py
index 18eac34..52e4407 100644
--- a/Backend/Application/Skills/FaultTreeSkill.py
+++ b/Backend/Application/Skills/FaultTreeSkill.py
@@ -46,7 +46,7 @@
                                 },
                                 "gate_type": {
                                     "type": "string",
-                                    "enum": ["AND", "OR"],
+                                    "enum": ["AND", "OR", "XOR", "INHIBIT", "PRIORITY_AND"],
                                     "description": "逻辑门类型，仅当 node_type 为 gate 时需要",
                                 },
                                 "remark": {
@@ -114,7 +114,7 @@
                                 },
                                 "gate_type": {
                                     "type": "string",
-                                    "enum": ["AND", "OR"],
+                                    "enum": ["AND", "OR", "XOR", "INHIBIT", "PRIORITY_AND"],
                                     "description": "逻辑门类型，仅 gate 节点需要",
                                 },
                                 "remark": {"type": "string", "description": "备注信息"},
diff --git a/Backend/Application/UseCases/FolderUseCase.py b/Backend/Application/UseCases/FolderUseCase.py
new file mode 100644
index 0000000..438aae5
--- /dev/null
+++ b/Backend/Application/UseCases/FolderUseCase.py
@@ -0,0 +1,63 @@
+"""文件夹用例层，处理创建、重命名、删除文件夹及文件归类的业务逻辑。"""
+import logging
+from Backend.Domain.Entities.folder import Folder
+from Backend.Application.Interfaces.IFolderRepository import IFolderRepository
+from Backend.Application.Interfaces.IFileRepository import IFileRepository
+
+logger = logging.getLogger(__name__)
+
+
+class FolderUseCase:
+    def __init__(
+        self,
+        folder_repository: IFolderRepository,
+        file_repository: IFileRepository,
+    ):
+        self._folder_repo = folder_repository
+        self._file_repo = file_repository
+
+    def create_folder(self, name: str) -> Folder:
+        existing = self._folder_repo.get_by_name(name)
+        if existing is not None:
+            raise ValueError(f"Folder already exists: {name}")
+        folder = Folder(name=name)
+        self._folder_repo.save(folder)
+        logger.info("Folder created: %s (%s)", folder.name, folder.id)
+        return folder
+
+    def rename_folder(self, folder_id: str, new_name: str) -> Folder:
+        folder = self._folder_repo.get_by_id(folder_id)
+        if folder is None:
+            raise ValueError(f"Folder not found: {folder_id}")
+        existing = self._folder_repo.get_by_name(new_name)
+        if existing is not None and existing.id != folder_id:
+            raise ValueError(f"Folder name already taken: {new_name}")
+        folder.rename(new_name)
+        self._folder_repo.update_name(folder_id, new_name)
+        logger.info("Folder renamed: %s -> %s", folder_id, new_name)
+        return folder
+
+    def list_folders(self) -> list[dict]:
+        folders = self._folder_repo.get_all()
+        result = []
+        for folder in folders:
+            files = self._file_repo.get_by_folder_id(folder.id)
+            folder_dict = folder.to_dict()
+            folder_dict["files"] = [f.to_dict() for f in files]
+            result.append(folder_dict)
+        return result
+
+    def delete_folder(self, folder_id: str) -> None:
+        folder = self._folder_repo.get_by_id(folder_id)
+        if folder is None:
+            raise ValueError(f"Folder not found: {folder_id}")
+        self._folder_repo.delete(folder_id)
+        logger.info("Folder deleted: %s (%s)", folder.name, folder_id)
+
+    def move_file_to_folder(self, file_id: str, folder_id: str | None) -> None:
+        if folder_id is not None:
+            folder = self._folder_repo.get_by_id(folder_id)
+            if folder is None:
+                raise ValueError(f"Folder not found: {folder_id}")
+        self._file_repo.update_folder(file_id, folder_id)
+        logger.info("File %s moved to folder %s", file_id, folder_id)
diff --git a/Backend/Domain/Entities/file.py b/Backend/Domain/Entities/file.py
index 3aae31c..4698286 100644
--- a/Backend/Domain/Entities/file.py
+++ b/Backend/Domain/Entities/file.py
@@ -12,12 +12,14 @@ def __init__(
         file_id: str | None = None,
         created_at: datetime | None = None,
         status: FileStatus = FileStatus.PENDING,
+        folder_id: str | None = None,
     ):
         self.id = file_id or str(uuid.uuid4())
         self.file_name = file_name
         self.file_type = file_type
         self.created_at = created_at or datetime.now()
         self.status = status
+        self.folder_id = folder_id
 
     def mark_embedded(self):
         self.status = FileStatus.EMBEDDED
@@ -32,4 +34,5 @@ def to_dict(self) -> dict:
             "file_type": self.file_type.value,
             "created_at": self.created_at.isoformat(),
             "status": self.status.value,
+            "folder_id": self.folder_id,
         }
diff --git a/Backend/Domain/Entities/folder.py b/Backend/Domain/Entities/folder.py
new file mode 100644
index 0000000..046b182
--- /dev/null
+++ b/Backend/Domain/Entities/folder.py
@@ -0,0 +1,25 @@
+"""文件夹领域实体，用于对上传文件进行分类管理。"""
+import uuid
+from datetime import datetime
+
+
+class Folder:
+    def __init__(
+        self,
+        name: str,
+        folder_id: str | None = None,
+        created_at: datetime | None = None,
+    ):
+        self.id = folder_id or str(uuid.uuid4())
+        self.name = name
+        self.created_at = created_at or datetime.now()
+
+    def rename(self, new_name: str):
+        self.name = new_name
+
+    def to_dict(self) -> dict:
+        return {
+            "id": self.id,
+            "name": self.name,
+            "created_at": self.created_at.isoformat(),
+        }
diff --git a/Backend/Infrastructure/persistence/FileRepository.py b/Backend/Infrastructure/persistence/FileRepository.py
index aee88c4..89bed2c 100644
--- a/Backend/Infrastructure/persistence/FileRepository.py
+++ b/Backend/Infrastructure/persistence/FileRepository.py
@@ -11,8 +11,8 @@ def save(self, file: File) -> None:
         conn = get_connection()
         try:
             conn.execute(
-                "INSERT INTO files (id, file_name, file_type, created_at, status) VALUES (?, ?, ?, ?, ?)",
-                (file.id, file.file_name, file.file_type.value, file.created_at.isoformat(), file.status.value),
+                "INSERT INTO files (id, file_name, file_type, created_at, status, folder_id) VALUES (?, ?, ?, ?, ?, ?)",
+                (file.id, file.file_name, file.file_type.value, file.created_at.isoformat(), file.status.value, file.folder_id),
             )
             conn.commit()
         finally:
@@ -52,6 +52,22 @@ def update_status(self, file_id: str, status: FileStatus) -> None:
         finally:
             conn.close()
 
+    def update_folder(self, file_id: str, folder_id: str | None) -> None:
+        conn = get_connection()
+        try:
+            conn.execute("UPDATE files SET folder_id = ? WHERE id = ?", (folder_id, file_id))
+            conn.commit()
+        finally:
+            conn.close()
+
+    def get_by_folder_id(self, folder_id: str) -> list[File]:
+        conn = get_connection()
+        try:
+            rows = conn.execute("SELECT * FROM files WHERE folder_id = ? ORDER BY created_at DESC", (folder_id,)).fetchall()
+            return [self._row_to_entity(row) for row in rows]
+        finally:
+            conn.close()
+
     @staticmethod
     def _row_to_entity(row) -> File:
         return File(
@@ -60,4 +76,5 @@ def _row_to_entity(row) -> File:
             file_type=FileType(row["file_type"]),
             created_at=datetime.fromisoformat(row["created_at"]),
             status=FileStatus(row["status"]),
+            folder_id=row["folder_id"],
         )
diff --git a/Backend/Infrastructure/persistence/FolderRepository.py b/Backend/Infrastructure/persistence/FolderRepository.py
new file mode 100644
index 0000000..c705089
--- /dev/null
+++ b/Backend/Infrastructure/persistence/FolderRepository.py
@@ -0,0 +1,71 @@
+"""文件夹仓储的 SQLite 实现，负责文件夹的增删改查持久化。"""
+from datetime import datetime
+from Backend.Application.Interfaces.IFolderRepository import IFolderRepository
+from Backend.Domain.Entities.folder import Folder
+from Backend.Infrastructure.persistence.database import get_connection
+
+
+class SQLiteFolderRepository(IFolderRepository):
+    def save(self, folder: Folder) -> None:
+        conn = get_connection()
+        try:
+            conn.execute(
+                "INSERT INTO folders (id, name, created_at) VALUES (?, ?, ?)",
+                (folder.id, folder.name, folder.created_at.isoformat()),
+            )
+            conn.commit()
+        finally:
+            conn.close()
+
+    def get_by_id(self, folder_id: str) -> Folder | None:
+        conn = get_connection()
+        try:
+            row = conn.execute("SELECT * FROM folders WHERE id = ?", (folder_id,)).fetchone()
+            if row is None:
+                return None
+            return self._row_to_entity(row)
+        finally:
+            conn.close()
+
+    def get_by_name(self, name: str) -> Folder | None:
+        conn = get_connection()
+        try:
+            row = conn.execute("SELECT * FROM folders WHERE name = ?", (name,)).fetchone()
+            if row is None:
+                return None
+            return self._row_to_entity(row)
+        finally:
+            conn.close()
+
+    def get_all(self) -> list[Folder]:
+        conn = get_connection()
+        try:
+            rows = conn.execute("SELECT * FROM folders ORDER BY created_at DESC").fetchall()
+            return [self._row_to_entity(row) for row in rows]
+        finally:
+            conn.close()
+
+    def update_name(self, folder_id: str, new_name: str) -> None:
+        conn = get_connection()
+        try:
+            conn.execute("UPDATE folders SET name = ? WHERE id = ?", (new_name, folder_id))
+            conn.commit()
+        finally:
+            conn.close()
+
+    def delete(self, folder_id: str) -> None:
+        conn = get_connection()
+        try:
+            conn.execute("UPDATE files SET folder_id = NULL WHERE folder_id = ?", (folder_id,))
+            conn.execute("DELETE FROM folders WHERE id = ?", (folder_id,))
+            conn.commit()
+        finally:
+            conn.close()
+
+    @staticmethod
+    def _row_to_entity(row) -> Folder:
+        return Folder(
+            folder_id=row["id"],
+            name=row["name"],
+            created_at=datetime.fromisoformat(row["created_at"]),
+        )
diff --git a/Backend/Infrastructure/persistence/database.py b/Backend/Infrastructure/persistence/database.py
index b9e84e7..af80bc6 100644
--- a/Backend/Infrastructure/persistence/database.py
+++ b/Backend/Infrastructure/persistence/database.py
@@ -10,7 +10,17 @@
     file_name TEXT NOT NULL,
     file_type TEXT NOT NULL,
     created_at TEXT NOT NULL,
-    status TEXT NOT NULL
+    status TEXT NOT NULL,
+    folder_id TEXT,
+    FOREIGN KEY (folder_id) REFERENCES folders(id)
+);
+"""
+
+_CREATE_FOLDERS_SQL = """
+CREATE TABLE IF NOT EXISTS folders (
+    id TEXT PRIMARY KEY,
+    name TEXT NOT NULL,
+    created_at TEXT NOT NULL
 );
 """
 
@@ -85,6 +95,7 @@ def init_db() -> None:
     conn = get_connection()
     try:
         with _lock:
+            conn.execute(_CREATE_FOLDERS_SQL)
             conn.execute(_CREATE_TABLE_SQL)
             conn.execute(_CREATE_CONVERSATIONS_SQL)
             conn.execute(_CREATE_CHAT_ROUNDS_SQL)
diff --git a/Backend/Web/Endpoints/FolderEndpoint.py b/Backend/Web/Endpoints/FolderEndpoint.py
new file mode 100644
index 0000000..8928a06
--- /dev/null
+++ b/Backend/Web/Endpoints/FolderEndpoint.py
@@ -0,0 +1,73 @@
+"""文件夹管理 REST API 端点，提供文件夹的增删改查及文件移动接口。"""
+from flask import Blueprint, request
+from Backend.Application.UseCases.FolderUseCase import FolderUseCase
+
+folder_bp = Blueprint("folders", __name__, url_prefix="/api/folders")
+
+
+def create_folder_blueprint(folder_use_case: FolderUseCase) -> Blueprint:
+
+    @folder_bp.route("", methods=["POST"])
+    def create_folder():
+        data = request.get_json()
+        if not data or not data.get("name"):
+            return {"error": "Folder name is required"}, 400
+        name = data["name"].strip()
+        if not name:
+            return {"error": "Folder name cannot be empty"}, 400
+        try:
+            folder = folder_use_case.create_folder(name)
+            return folder.to_dict(), 201
+        except ValueError as e:
+            return {"error": str(e)}, 409
+
+    @folder_bp.route("", methods=["GET"])
+    def list_folders():
+        folders = folder_use_case.list_folders()
+        return folders
+
+    @folder_bp.route("/<folder_id>", methods=["PATCH"])
+    def rename_folder(folder_id: str):
+        data = request.get_json()
+        if not data or not data.get("name"):
+            return {"error": "New folder name is required"}, 400
+        new_name = data["name"].strip()
+        if not new_name:
+            return {"error": "Folder name cannot be empty"}, 400
+        try:
+            folder = folder_use_case.rename_folder(folder_id, new_name)
+            return folder.to_dict(), 200
+        except ValueError as e:
+            return {"error": str(e)}, 404
+
+    @folder_bp.route("/<folder_id>", methods=["DELETE"])
+    def delete_folder(folder_id: str):
+        try:
+            folder_use_case.delete_folder(folder_id)
+            return {"message": "Folder deleted"}, 200
+        except ValueError as e:
+            return {"error": str(e)}, 404
+
+    @folder_bp.route("/<folder_id>/files", methods=["POST"])
+    def move_file_to_folder(folder_id: str):
+        data = request.get_json()
+        if not data or not data.get("file_id"):
+            return {"error": "file_id is required"}, 400
+        try:
+            folder_use_case.move_file_to_folder(data["file_id"], folder_id)
+            return {"message": "File moved to folder"}, 200
+        except ValueError as e:
+            return {"error": str(e)}, 404
+
+    @folder_bp.route("/unfile", methods=["POST"])
+    def remove_file_from_folder():
+        data = request.get_json()
+        if not data or not data.get("file_id"):
+            return {"error": "file_id is required"}, 400
+        try:
+            folder_use_case.move_file_to_folder(data["file_id"], None)
+            return {"message": "File removed from folder"}, 200
+        except ValueError as e:
+            return {"error": str(e)}, 404
+
+    return folder_bp
diff --git a/Backend/Web/app_factory.py b/Backend/Web/app_factory.py
index 8bedb5a..068c3b1 100644
--- a/Backend/Web/app_factory.py
+++ b/Backend/Web/app_factory.py
@@ -4,6 +4,7 @@
 from Backend.Infrastructure.persistence.LocalFileStorage import LocalFileStorage
 from Backend.Infrastructure.persistence.ConversationRepository import SQLiteConversationRepository
 from Backend.Infrastructure.persistence.FaultTreeRepository import SQLiteFaultTreeRepository
+from Backend.Infrastructure.persistence.FolderRepository import SQLiteFolderRepository
 from Backend.Infrastructure.document.DocumentProcessorPro import DocumentProcessorPro
 from Backend.Infrastructure.vectorstore.ChromaVectorStoreRepository import ChromaVectorStoreRepository
 from Backend.Infrastructure.llm.LLMService import LLMService
@@ -12,10 +13,12 @@
 from Backend.Application.UseCases.ChatUseCase import ChatUseCase
 from Backend.Application.UseCases.DeleteConversationUseCase import DeleteConversationUseCase
 from Backend.Application.UseCases.FaultTreeUseCase import FaultTreeUseCase
+from Backend.Application.UseCases.FolderUseCase import FolderUseCase
 from Backend.Application.Skills.FaultTreeSkill import FaultTreeSkill
 from Backend.Web.Endpoints.FileEndpoint import create_file_blueprint
 from Backend.Web.Endpoints.ChatEndpoint import create_chat_blueprint
 from Backend.Web.Endpoints.FaultTreeEndpoint import create_fault_tree_blueprint
+from Backend.Web.Endpoints.FolderEndpoint import create_folder_blueprint
 
 
 def create_app() -> Flask:
@@ -31,6 +34,7 @@ def create_app() -> Flask:
     vector_store_repository = ChromaVectorStoreRepository(persist_directory="db")
     conversation_repository = SQLiteConversationRepository()
     fault_tree_repository = SQLiteFaultTreeRepository()
+    folder_repository = SQLiteFolderRepository()
     llm_service = LLMService()
 
     # Skills 组装
@@ -61,6 +65,10 @@ def create_app() -> Flask:
     fault_tree_use_case = FaultTreeUseCase(
         fault_tree_repository=fault_tree_repository,
     )
+    folder_use_case = FolderUseCase(
+        folder_repository=folder_repository,
+        file_repository=file_repository,
+    )
 
     # 注册 Blueprint
     file_bp = create_file_blueprint(import_use_case, delete_use_case, file_repository)
@@ -72,4 +80,7 @@ def create_app() -> Flask:
     fault_tree_bp = create_fault_tree_blueprint(fault_tree_use_case)
     app.register_blueprint(fault_tree_bp)
 
+    folder_bp = create_folder_blueprint(folder_use_case)
+    app.register_blueprint(folder_bp)
+
     return app
diff --git a/tests/test_folder_api.py b/tests/test_folder_api.py
new file mode 100644
index 0000000..02c922a
--- /dev/null
+++ b/tests/test_folder_api.py
@@ -0,0 +1,326 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+"""文件夹管理模块 API 测试 —— 覆盖文件夹增删改查及文件归类操作"""
+
+import os
+import time
+import requests
+
+BASE_URL = "http://127.0.0.1:8080"
+TEST_DIR = os.path.dirname(os.path.abspath(__file__))
+
+
+# ────────────────── 辅助函数 ──────────────────
+
+def _create_test_file(filename: str, content: str) -> str:
+    filepath = os.path.join(TEST_DIR, filename)
+    with open(filepath, "w", encoding="utf-8") as f:
+        f.write(content)
+    return filepath
+
+
+def _cleanup_test_file(filename: str):
+    filepath = os.path.join(TEST_DIR, filename)
+    if os.path.exists(filepath):
+        os.remove(filepath)
+
+
+def _upload_file(filename: str, content: str) -> dict:
+    """上传一个测试文件并等待向量化完成，返回文件实体 dict。"""
+    filepath = _create_test_file(filename, content)
+    try:
+        with open(filepath, "rb") as f:
+            resp = requests.post(
+                f"{BASE_URL}/api/files",
+                files={"file": (filename, f, "text/plain")},
+                timeout=10,
+            )
+        assert resp.status_code == 202, f"上传失败: {resp.status_code} {resp.text}"
+        file_entity = resp.json()
+
+        # 等待向量化完成（最多 60 秒）
+        for _ in range(60):
+            updated = requests.get(f"{BASE_URL}/api/files", timeout=5).json()
+            match = [fe for fe in updated if fe["id"] == file_entity["id"]]
+            if match and match[0]["status"] in ("embedded", "failed"):
+                return match[0]
+            time.sleep(1)
+        return file_entity
+    finally:
+        _cleanup_test_file(filename)
+
+
+def _delete_file(file_name: str):
+    requests.delete(f"{BASE_URL}/api/files/{file_name}", timeout=10)
+
+
+# ────────────────── 文件夹 CRUD 测试 ──────────────────
+
+def test_create_folder():
+    """测试 1: 创建文件夹"""
+    print("\n" + "=" * 60)
+    print("TEST 1: POST /api/folders — 创建文件夹")
+    print("=" * 60)
+
+    resp = requests.post(f"{BASE_URL}/api/folders", json={"name": "安全分析"}, timeout=10)
+    result = resp.json()
+
+    print(f"[✓] 状态码: {resp.status_code}")
+    print(f"[✓] 文件夹: id={result.get('id')}, name={result.get('name')}")
+
+    assert resp.status_code == 201
+    assert result["name"] == "安全分析"
+    return result["id"]
+
+
+def test_create_folder_duplicate():
+    """测试 2: 创建重名文件夹应返回 409"""
+    print("\n" + "=" * 60)
+    print("TEST 2: POST /api/folders — 重名文件夹")
+    print("=" * 60)
+
+    resp = requests.post(f"{BASE_URL}/api/folders", json={"name": "安全分析"}, timeout=10)
+    print(f"[✓] 状态码: {resp.status_code}")
+    print(f"[✓] 错误: {resp.json().get('error')}")
+    assert resp.status_code == 409
+
+
+def test_create_folder_empty():
+    """测试 3: 空名称应返回 400"""
+    print("\n" + "=" * 60)
+    print("TEST 3: POST /api/folders — 空名称")
+    print("=" * 60)
+
+    resp = requests.post(f"{BASE_URL}/api/folders", json={"name": ""}, timeout=10)
+    print(f"[✓] 状态码: {resp.status_code}")
+    print(f"[✓] 错误: {resp.json().get('error')}")
+    assert resp.status_code == 400
+
+
+def test_list_folders():
+    """测试 4: 获取文件夹列表"""
+    print("\n" + "=" * 60)
+    print("TEST 4: GET /api/folders — 文件夹列表")
+    print("=" * 60)
+
+    resp = requests.get(f"{BASE_URL}/api/folders", timeout=10)
+    folders = resp.json()
+
+    print(f"[✓] 状态码: {resp.status_code}")
+    print(f"[✓] 文件夹数: {len(folders)}")
+    for f in folders:
+        print(f"    - {f['name']} (文件数: {len(f.get('files', []))})")
+
+    assert resp.status_code == 200
+    assert isinstance(folders, list)
+    assert len(folders) >= 1
+
+
+def test_rename_folder(folder_id: str):
+    """测试 5: 重命名文件夹"""
+    print("\n" + "=" * 60)
+    print("TEST 5: PATCH /api/folders/<id> — 重命名")
+    print("=" * 60)
+
+    resp = requests.patch(
+        f"{BASE_URL}/api/folders/{folder_id}",
+        json={"name": "故障分析"},
+        timeout=10,
+    )
+    result = resp.json()
+
+    print(f"[✓] 状态码: {resp.status_code}")
+    print(f"[✓] 新名称: {result.get('name')}")
+
+    assert resp.status_code == 200
+    assert result["name"] == "故障分析"
+
+
+def test_rename_nonexistent():
+    """测试 6: 重命名不存在的文件夹"""
+    print("\n" + "=" * 60)
+    print("TEST 6: PATCH /api/folders/<不存在> — 404")
+    print("=" * 60)
+
+    resp = requests.patch(
+        f"{BASE_URL}/api/folders/no-such-id",
+        json={"name": "x"},
+        timeout=10,
+    )
+    print(f"[✓] 状态码: {resp.status_code}")
+    assert resp.status_code == 404
+
+
+# ────────────────── 文件归类测试 ──────────────────
+
+def test_move_file_to_folder(folder_id: str, file_id: str):
+    """测试 7: 将文件移入文件夹"""
+    print("\n" + "=" * 60)
+    print("TEST 7: POST /api/folders/<id>/files — 移入文件")
+    print("=" * 60)
+
+    resp = requests.post(
+        f"{BASE_URL}/api/folders/{folder_id}/files",
+        json={"file_id": file_id},
+        timeout=10,
+    )
+    print(f"[✓] 状态码: {resp.status_code}")
+    print(f"[✓] {resp.json()}")
+    assert resp.status_code == 200
+
+
+def test_verify_file_in_folder(folder_id: str, file_id: str):
+    """测试 8: 验证文件已出现在文件夹列表中"""
+    print("\n" + "=" * 60)
+    print("TEST 8: GET /api/folders — 验证文件归类")
+    print("=" * 60)
+
+    resp = requests.get(f"{BASE_URL}/api/folders", timeout=10)
+    folders = resp.json()
+    target = [f for f in folders if f["id"] == folder_id]
+
+    assert len(target) == 1, "目标文件夹未找到"
+    file_ids = [fi["id"] for fi in target[0].get("files", [])]
+    print(f"[✓] 文件夹 '{target[0]['name']}' 中的文件: {file_ids}")
+    assert file_id in file_ids, "文件未出现在文件夹中"
+    print(f"[✓] 文件 {file_id} 已确认在文件夹内")
+
+
+def test_file_list_has_folder_id(file_id: str, folder_id: str):
+    """测试 9: 文件列表中 folder_id 字段正确"""
+    print("\n" + "=" * 60)
+    print("TEST 9: GET /api/files — 文件的 folder_id 字段")
+    print("=" * 60)
+
+    resp = requests.get(f"{BASE_URL}/api/files", timeout=10)
+    files = resp.json()
+    target = [f for f in files if f["id"] == file_id]
+
+    assert len(target) == 1
+    print(f"[✓] 文件 folder_id = {target[0].get('folder_id')}")
+    assert target[0].get("folder_id") == folder_id
+
+
+def test_remove_file_from_folder(file_id: str):
+    """测试 10: 将文件移出文件夹"""
+    print("\n" + "=" * 60)
+    print("TEST 10: POST /api/folders/unfile — 移出文件")
+    print("=" * 60)
+
+    resp = requests.post(
+        f"{BASE_URL}/api/folders/unfile",
+        json={"file_id": file_id},
+        timeout=10,
+    )
+    print(f"[✓] 状态码: {resp.status_code}")
+    assert resp.status_code == 200
+
+    # 确认 folder_id 已清空
+    files = requests.get(f"{BASE_URL}/api/files", timeout=10).json()
+    target = [f for f in files if f["id"] == file_id]
+    assert target[0].get("folder_id") is None
+    print(f"[✓] 文件 folder_id 已清空")
+
+
+# ────────────────── 删除文件夹测试 ──────────────────
+
+def test_delete_folder(folder_id: str):
+    """测试 11: 删除文件夹"""
+    print("\n" + "=" * 60)
+    print("TEST 11: DELETE /api/folders/<id> — 删除文件夹")
+    print("=" * 60)
+
+    resp = requests.delete(f"{BASE_URL}/api/folders/{folder_id}", timeout=10)
+    print(f"[✓] 状态码: {resp.status_code}")
+    assert resp.status_code == 200
+
+    # 确认已删除
+    folders = requests.get(f"{BASE_URL}/api/folders", timeout=10).json()
+    assert all(f["id"] != folder_id for f in folders)
+    print(f"[✓] 文件夹已从列表中移除")
+
+
+def test_delete_nonexistent():
+    """测试 12: 删除不存在的文件夹"""
+    print("\n" + "=" * 60)
+    print("TEST 12: DELETE /api/folders/<不存在> — 404")
+    print("=" * 60)
+
+    resp = requests.delete(f"{BASE_URL}/api/folders/no-such-id", timeout=10)
+    print(f"[✓] 状态码: {resp.status_code}")
+    assert resp.status_code == 404
+
+
+# ────────────────── 主流程 ──────────────────
+
+def main():
+    print("\n╔" + "=" * 58 + "╗")
+    print("║" + "  文件夹管理 + 文件归类 — API 综合测试".center(50) + "║")
+    print("╚" + "=" * 58 + "╝")
+
+    passed = 0
+    failed = 0
+    folder_id = None
+    file_entity = None
+
+    def _run(name, fn, *args):
+        nonlocal passed, failed
+        try:
+            result = fn(*args)
+            passed += 1
+            return result
+        except Exception as e:
+            print(f"[✗ FAIL] {name}: {e}")
+            failed += 1
+            return None
+
+    # ── 上传一个测试文件 ──
+    print("\n>>> 准备：上传测试文件 <<<")
+    file_entity = _run("上传测试文件", _upload_file, "folder_test.txt", "文件夹功能测试文本。\n" * 20)
+    file_id = file_entity["id"] if file_entity else None
+    file_name = file_entity["file_name"] if file_entity else None
+    if file_entity:
+        print(f"[✓] 测试文件就绪: id={file_id}, status={file_entity['status']}")
+
+    # ── 文件夹 CRUD ──
+    print("\n>>> 文件夹 CRUD 测试 <<<")
+    folder_id = _run("创建文件夹", test_create_folder)
+    _run("重名文件夹", test_create_folder_duplicate)
+    _run("空名称", test_create_folder_empty)
+    _run("文件夹列表", test_list_folders)
+    if folder_id:
+        _run("重命名", test_rename_folder, folder_id)
+    _run("重命名不存在", test_rename_nonexistent)
+
+    # ── 文件归类 ──
+    if folder_id and file_id:
+        print("\n>>> 文件归类测试 <<<")
+        _run("移入文件", test_move_file_to_folder, folder_id, file_id)
+        _run("验证归类", test_verify_file_in_folder, folder_id, file_id)
+        _run("文件 folder_id", test_file_list_has_folder_id, file_id, folder_id)
+        _run("移出文件", test_remove_file_from_folder, file_id)
+    else:
+        print("\n[⚠ SKIP] 缺少文件夹或文件，跳过归类测试")
+
+    # ── 删除 ──
+    print("\n>>> 删除测试 <<<")
+    if folder_id:
+        _run("删除文件夹", test_delete_folder, folder_id)
+    _run("删除不存在", test_delete_nonexistent)
+
+    # ── 清理测试文件 ──
+    if file_name:
+        _delete_file(file_name)
+        print(f"\n[清理] 已删除测试文件: {file_name}")
+
+    # ── 汇总 ──
+    print("\n" + "=" * 60)
+    print(f"结果: {passed} 通过, {failed} 失败")
+    print("=" * 60 + "\n")
+
+    return failed == 0
+
+
+if __name__ == "__main__":
+    success = main()
+    exit(0 if success else 1)
diff --git a/uploads/folder_test.txt b/uploads/folder_test.txt
new file mode 100644
index 0000000..f15315d
--- /dev/null
+++ b/uploads/folder_test.txt
@@ -0,0 +1,20 @@
+文件夹功能测试文本。
+文件夹功能测试文本。
+文件夹功能测试文本。
+文件夹功能测试文本。
+文件夹功能测试文本。
+文件夹功能测试文本。
+文件夹功能测试文本。
+文件夹功能测试文本。
+文件夹功能测试文本。
+文件夹功能测试文本。
+文件夹功能测试文本。
+文件夹功能测试文本。
+文件夹功能测试文本。
+文件夹功能测试文本。
+文件夹功能测试文本。
+文件夹功能测试文本。
+文件夹功能测试文本。
+文件夹功能测试文本。
+文件夹功能测试文本。
+文件夹功能测试文本。