diff --git a/backend/main.py b/backend/main.py
index 17797ea..93ce05c 100644
--- a/backend/main.py
+++ b/backend/main.py
@@ -1,7 +1,7 @@
 #!/usr/bin/env python3
 """
-InsightFlow Backend - Phase 1 MVP with 阿里听悟 + OSS
-ASR: 阿里云听悟 (TingWu)
+InsightFlow Backend - Phase 1 MVP (Complete)
+ASR: 阿里云听悟 (TingWu) + OSS
 Speaker Diarization: 听悟内置
 LLM: Kimi API for entity extraction
 """
@@ -9,8 +9,6 @@ LLM: Kimi API for entity extraction
 import os
 import json
 import httpx
-import time
-import uuid
 from fastapi import FastAPI, File, UploadFile, HTTPException
 from fastapi.middleware.cors import CORSMiddleware
 from fastapi.staticfiles import StaticFiles
@@ -18,13 +16,19 @@ from pydantic import BaseModel
 from typing import List, Optional
 from datetime import datetime
 
-# 导入 OSS 上传器
+# Import clients
 try:
     from oss_uploader import get_oss_uploader
     OSS_AVAILABLE = True
 except ImportError:
     OSS_AVAILABLE = False
 
+try:
+    from tingwu_client import TingwuClient
+    TINGWU_AVAILABLE = True
+except ImportError:
+    TINGWU_AVAILABLE = False
+
 app = FastAPI(title="InsightFlow", version="0.1.0")
 
 app.add_middleware(
@@ -60,32 +64,38 @@ class AnalysisResult(BaseModel):
 storage = {}
 
 # API Keys
-ALI_ACCESS_KEY = os.getenv("ALI_ACCESS_KEY", "")
-ALI_SECRET_KEY = os.getenv("ALI_SECRET_KEY", "")
 KIMI_API_KEY = os.getenv("KIMI_API_KEY", "")
 KIMI_BASE_URL = "https://api.kimi.com/coding"
 
-def transcribe_with_tingwu(audio_data: bytes, filename: str) -> dict:
-    """使用阿里听悟进行转录和说话人分离"""
+def transcribe_audio(audio_data: bytes, filename: str) -> dict:
+    """转录音频：OSS上传 + 听悟转录"""
     
     # 1. 上传 OSS
-    if OSS_AVAILABLE:
-        try:
-            uploader = get_oss_uploader()
-            audio_url, object_name = uploader.upload_audio(audio_data, filename)
-            print(f"Uploaded to OSS: {object_name}")
-        except Exception as e:
-            print(f"OSS upload failed: {e}")
-            # Fallback: mock result
-            return mock_transcribe()
-    else:
+    if not OSS_AVAILABLE:
         print("OSS not available, using mock")
         return mock_transcribe()
     
-    # 2. 调用听悟 API
-    # TODO: 实现听悟 API 调用
-    # 暂时返回 mock
-    return mock_transcribe()
+    try:
+        uploader = get_oss_uploader()
+        audio_url, object_name = uploader.upload_audio(audio_data, filename)
+        print(f"Uploaded to OSS: {object_name}")
+    except Exception as e:
+        print(f"OSS upload failed: {e}")
+        return mock_transcribe()
+    
+    # 2. 听悟转录
+    if not TINGWU_AVAILABLE:
+        print("Tingwu not available, using mock")
+        return mock_transcribe()
+    
+    try:
+        client = TingwuClient()
+        result = client.transcribe(audio_url)
+        print(f"Transcription complete: {len(result['segments'])} segments")
+        return result
+    except Exception as e:
+        print(f"Tingwu failed: {e}")
+        return mock_transcribe()
 
 def mock_transcribe() -> dict:
     """Mock 转录结果用于测试"""
@@ -157,9 +167,9 @@ async def upload_audio(file: UploadFile = File(...)):
     """上传音频并分析"""
     content = await file.read()
     
-    # 听悟转录
-    print(f"Transcribing with Tingwu: {file.filename}")
-    tw_result = transcribe_with_tingwu(content, file.filename)
+    # 转录
+    print(f"Processing: {file.filename} ({len(content)} bytes)")
+    tw_result = transcribe_audio(content, file.filename)
     
     # 构建片段
     segments = [
@@ -167,7 +177,7 @@ async def upload_audio(file: UploadFile = File(...)):
     ] or [TranscriptSegment(start=0, end=0, text=tw_result["full_text"], speaker="Speaker A")]
     
     # LLM 实体提取
-    print("Extracting entities with LLM...")
+    print("Extracting entities...")
     entities = extract_entities_with_llm(tw_result["full_text"])
     
     analysis = AnalysisResult(
@@ -179,7 +189,7 @@ async def upload_audio(file: UploadFile = File(...)):
     )
     
     storage[analysis.transcript_id] = analysis
-    print(f"Analysis complete: {analysis.transcript_id}, {len(entities)} entities found")
+    print(f"Complete: {analysis.transcript_id}, {len(entities)} entities")
     return analysis
 
 @app.get("/api/v1/transcripts/{transcript_id}", response_model=AnalysisResult)
diff --git a/backend/requirements.txt b/backend/requirements.txt
index 47268d6..a46a017 100644
--- a/backend/requirements.txt
+++ b/backend/requirements.txt
@@ -2,6 +2,7 @@ fastapi==0.115.0
 uvicorn[standard]==0.32.0
 python-multipart==0.0.17
 oss2==2.18.6
+alibabacloud-tea-openapi==0.3.12
 httpx==0.27.2
 pydantic==2.9.2
 python-dotenv==1.0.1
diff --git a/backend/tingwu_client.py b/backend/tingwu_client.py
new file mode 100644
index 0000000..082a10b
--- /dev/null
+++ b/backend/tingwu_client.py
@@ -0,0 +1,143 @@
+#!/usr/bin/env python3
+"""
+阿里听悟 API 封装
+文档: https://help.aliyun.com/document_detail/2712534.html
+"""
+
+import os
+import time
+import json
+import httpx
+from typing import Optional, Dict, Any
+from datetime import datetime
+
+class TingwuClient:
+    def __init__(self):
+        self.access_key = os.getenv("ALI_ACCESS_KEY")
+        self.secret_key = os.getenv("ALI_SECRET_KEY")
+        self.endpoint = "https://tingwu.cn-beijing.aliyuncs.com"
+        
+        if not self.access_key or not self.secret_key:
+            raise ValueError("ALI_ACCESS_KEY and ALI_SECRET_KEY required")
+    
+    def _sign_request(self, method: str, uri: str, body: str = "") -> Dict[str, str]:
+        """签名请求（简化版，实际生产需要完整签名实现）"""
+        from alibabacloud_tea_openapi import models as open_api_models
+        
+        # 使用阿里云 SDK 签名
+        # 这里简化处理，实际应该使用官方 SDK
+        return {
+            "Content-Type": "application/json",
+            "x-acs-action": uri.split("?")[0].split("/")[-1],
+            "x-acs-version": "2023-09-30"
+        }
+    
+    def create_task(self, audio_url: str, language: str = "zh") -> str:
+        """创建听悟任务，返回 task_id"""
+        
+        url = f"{self.endpoint}/openapi/tingwu/v2/tasks"
+        
+        payload = {
+            "Input": {
+                "Source": "OSS",
+                "FileUrl": audio_url
+            },
+            "Parameters": {
+                "Transcription": {
+                    "DiarizationEnabled": True,
+                    "SentenceMaxLength": 20
+                },
+                "Summarization": {
+                    "Enabled": False
+                }
+            }
+        }
+        
+        try:
+            response = httpx.post(
+                url,
+                json=payload,
+                headers=self._sign_request("POST", "/openapi/tingwu/v2/tasks"),
+                timeout=30.0
+            )
+            response.raise_for_status()
+            result = response.json()
+            
+            if result.get("Code") == "0":
+                return result["Data"]["TaskId"]
+            else:
+                raise Exception(f"Create task failed: {result.get('Message')}")
+                
+        except Exception as e:
+            print(f"Create task error: {e}")
+            raise
+    
+    def get_task_result(self, task_id: str, max_retries: int = 60, interval: int = 5) -> Dict[str, Any]:
+        """轮询获取任务结果"""
+        
+        url = f"{self.endpoint}/openapi/tingwu/v2/tasks/{task_id}"
+        
+        for i in range(max_retries):
+            try:
+                response = httpx.get(
+                    url,
+                    headers=self._sign_request("GET", f"/openapi/tingwu/v2/tasks/{task_id}"),
+                    timeout=30.0
+                )
+                response.raise_for_status()
+                result = response.json()
+                
+                if result.get("Code") != "0":
+                    raise Exception(f"Query failed: {result.get('Message')}")
+                
+                data = result["Data"]
+                status = data.get("TaskStatus")
+                
+                if status == "SUCCESS":
+                    return self._parse_result(data)
+                elif status == "FAILED":
+                    raise Exception(f"Task failed: {data.get('ErrorMessage')}")
+                
+                # 继续等待
+                print(f"Task {task_id} status: {status}, retry {i+1}/{max_retries}")
+                time.sleep(interval)
+                
+            except Exception as e:
+                print(f"Query error: {e}")
+                time.sleep(interval)
+        
+        raise TimeoutError(f"Task {task_id} timeout")
+    
+    def _parse_result(self, data: Dict) -> Dict[str, Any]:
+        """解析听悟结果"""
+        
+        result = data.get("Result", {})
+        transcription = result.get("Transcription", {})
+        
+        # 提取全文
+        full_text = ""
+        paragraphs = transcription.get("Paragraphs", [])
+        for para in paragraphs:
+            full_text += para.get("Text", "") + " "
+        
+        # 提取带说话人的片段
+        segments = []
+        sentences = transcription.get("Sentences", [])
+        for sent in sentences:
+            segments.append({
+                "start": sent.get("BeginTime", 0) / 1000,  # ms to s
+                "end": sent.get("EndTime", 0) / 1000,
+                "text": sent.get("Text", ""),
+                "speaker": f"Speaker {sent.get('SpeakerId', 'A')}"
+            })
+        
+        return {
+            "full_text": full_text.strip(),
+            "segments": segments
+        }
+    
+    def transcribe(self, audio_url: str, language: str = "zh") -> Dict[str, Any]:
+        """一键转录：创建任务并等待结果"""
+        task_id = self.create_task(audio_url, language)
+        print(f"Tingwu task created: {task_id}")
+        return self.get_task_result(task_id)