diff --git a/Src/Asp.NetCore2/MongoDbTest/UnitTest/InsertOrUpdate.cs b/Src/Asp.NetCore2/MongoDbTest/UnitTest/InsertOrUpdate.cs
index 0f01b5357..fdbef910e 100644
--- a/Src/Asp.NetCore2/MongoDbTest/UnitTest/InsertOrUpdate.cs
+++ b/Src/Asp.NetCore2/MongoDbTest/UnitTest/InsertOrUpdate.cs
@@ -14,9 +14,17 @@ namespace MongoDbTest
         internal static void Init()
         {
             var db = DBHelper.DbHelper.GetNewDb();
-            db.CodeFirst.InitTables<Student>(); 
+            db.CodeFirst.InitTables<Student>();
+            db.DbMaintenance.TruncateTable<Student>();
             db.Storageable(new Student() { Name = "a", SchoolId = "1", CreateDateTime = DateTime.Now })
                 .ExecuteCommand();
+            var datas=db.Queryable<Student>().ToList();
+            if (datas.Count != 1) Cases.ThrowUnitError();
+            datas.First().Name = "aaa";
+            db.Storageable(datas).ExecuteCommand();
+            var datas2 = db.Queryable<Student>().ToList();
+            if (datas2.Count != 1) Cases.ThrowUnitError();
+            if (datas2.First().Name != "aaa") Cases.ThrowUnitError();
         }
         [SqlSugar.SugarTable("UnitStudent1zzsds3z1")]
         public class Student : MongoDbBase
diff --git a/Src/Asp.NetCore2/SqlSugar.MongoDbCore/MongoDb/Queryable/MongoDbQueryable.cs b/Src/Asp.NetCore2/SqlSugar.MongoDbCore/MongoDb/Queryable/MongoDbQueryable.cs
index bed898c01..a7b8828f5 100644
--- a/Src/Asp.NetCore2/SqlSugar.MongoDbCore/MongoDb/Queryable/MongoDbQueryable.cs
+++ b/Src/Asp.NetCore2/SqlSugar.MongoDbCore/MongoDb/Queryable/MongoDbQueryable.cs
@@ -43,6 +43,10 @@ namespace SqlSugar.MongoDb
                         }
                         else
                         {
+                            if (column.IsPrimarykey&& value!=null) 
+                            {
+                                value = ObjectId.Parse(value?.ToString());
+                            }
                             bsonValue = BsonValue.Create(value);
                         }