diff --git a/PythonProject/api/student_api.py b/PythonProject/api/student_api.py
index 981de80..6cbed4a 100644
--- a/PythonProject/api/student_api.py
+++ b/PythonProject/api/student_api.py
@@ -1,4 +1,4 @@
-from fastapi import APIRouter,Depends,HTTPException
+from fastapi import APIRouter,HTTPException
 from dao.student_dao import *
 from schema.student_schema import *
 from util.database import get_db
@@ -33,10 +33,10 @@ def update_students(s:StudentRequest
                     ,db=Depends(get_db)):
     d = s.model_dump(exclude_unset=True)
     if not d:
-        raise HTTPException(status_code=400, detail='更新内容不能为空！')
+        raise HTTPException(status_code=400, detail='更新内容不能为空')
     r = update_student_dao( stu_id=stu_id,update_data=d,db=db )
     if not r:
-        raise HTTPException(status_code=500, detail='没有更新！')
+        raise HTTPException(status_code=500, detail='没有更新')
     return {'code':200,'totals':r,'detail':'更新成功'}
 
 @StudentAPI.delete('/{stu_id}',tags=['学⽣基本信息管理模块'],summary='学生信息删除接口',description='删除学生信息')
@@ -50,8 +50,12 @@ def del_students(stu_id:int
 @StudentAPI.post('/students',tags=['学⽣基本信息管理模块'],response_model=StugetResponse,summary='学生信息新增接口',description='新增学生信息')
 def add_students(s:StudentRequest
                  ,db=Depends(get_db)):
-    d=s.model_dump(exclude_unset=True)
-    stu_new=add_student_dao(o=d,db=db)
-    if not stu_new:
-        raise HTTPException(status_code=404,detail='添加失败')
-    return stu_new
+    d = s.model_dump(exclude_unset=True)
+    if not d:
+        raise HTTPException(status_code=400, detail='添加内容不能为空')
+    r = add_student_dao( o=d, db=db)
+    if r == 'conflict':
+        raise HTTPException(status_code=409, detail='身份证号已存在，请勿重复添加')
+    if r == 'error':
+        raise HTTPException(status_code=500, detail='更添加失败，请稍后重试')
+    return r
diff --git a/PythonProject/dao/student_dao.py b/PythonProject/dao/student_dao.py
index 9f755ac..0822d9d 100644
--- a/PythonProject/dao/student_dao.py
+++ b/PythonProject/dao/student_dao.py
@@ -1,19 +1,28 @@
-from fastapi import Depends
-from util.database import get_db
 from model.all_model import Student_Model
 from typing import List, Optional, Dict, Any
 from datetime import datetime
+from sqlalchemy.exc import IntegrityError
 
 def add_student_dao(o,db):
+    if o.get('id_card'):
+        conflict = (db.query(Student_Model)
+                    .filter(Student_Model.id_card == o['id_card'],
+                            Student_Model.delete_status == 0)
+                    .first())
+        if conflict:
+            return 'conflict'
     try:
-        o1 = Student_Model( **o)
-        db.add(o1)
+        o2 = Student_Model(**o)
+        db.add(o2)
         db.commit()
-        stu_id=o1.stu_id
-        return db.query(Student_Model).filter(Student_Model.stu_id == stu_id).first()
-    except:
+        db.refresh(o2)  # 回填自增的 stu_id
+        return o2
+    except IntegrityError:
         db.rollback()
-        return None
+        return 'conflict'
+    except Exception:
+        db.rollback()
+        return 'error'
 
 def delete_student_dao(stu_id,db):
     try:
@@ -28,14 +37,14 @@ def delete_student_dao(stu_id,db):
 
 def update_student_dao(stu_id,update_data,db):
     try:
-        rows = (db.query( Student_Model )
-                .filter( Student_Model.stu_id == stu_id,Student_Model.delete_status == 0)
-                .update( update_data ))
-        db.commit()
+        rows=(db.query(Student_Model)
+              .fiter(Student_Model.stu_id == stu_id,Student_Model.delete_status == 0)
+              .update(update_data))
     except:
         db.rollback()
         return False
     else:
+        db.commit()
         return rows
 
 def get_student_dao(stu_id:Optional[int]
diff --git a/PythonProject/model/all_model.py b/PythonProject/model/all_model.py
index fb48980..3fe8237 100644
--- a/PythonProject/model/all_model.py
+++ b/PythonProject/model/all_model.py
@@ -23,6 +23,8 @@ class Student_Model(Base):
 
     native_place=Column(String(200),comment='籍贯')
 
+    id_card=Column(String(18),unique=True,comment='身份证号')
+
     birthday=Column(DATE,comment='生日')
 
     school=Column(String(100),comment='毕业学校')
diff --git a/PythonProject/schema/student_schema.py b/PythonProject/schema/student_schema.py
index 58894ec..f699b21 100644
--- a/PythonProject/schema/student_schema.py
+++ b/PythonProject/schema/student_schema.py
@@ -9,6 +9,7 @@ class StudentRequest(BaseModel):
     stu_name:str
     age:int |None = None
     gender:str |None = None
+    id_card:str
     native_place:str |None = None
     birthday:date |None = None
     school:str |None = None
@@ -57,6 +58,7 @@ class StugetResponse(BaseModel):
     stu_name: str | None = None
     age: int | None = None
     gender: str | None = None
+    id_card: str
     native_place: str | None = None
     birthday: date | None = None
     school: str | None = None
@@ -81,4 +83,6 @@ class StudentPageResponse(BaseModel):
     page: int
     page_size: int
     totals: int
-    data: List[StugetResponse]
\ No newline at end of file
+    data: List[StugetResponse]
+
+