diff --git a/SqlSugar/Abstract/DbProvider/SqlBuilderProvider/DMLBuilder/DeleteBuilder.cs b/SqlSugar/Abstract/DbProvider/SqlBuilderProvider/DMLBuilder/DeleteBuilder.cs
index eca2cacbf..c13b7312f 100644
--- a/SqlSugar/Abstract/DbProvider/SqlBuilderProvider/DMLBuilder/DeleteBuilder.cs
+++ b/SqlSugar/Abstract/DbProvider/SqlBuilderProvider/DMLBuilder/DeleteBuilder.cs
@@ -33,11 +33,44 @@ namespace SqlSugar
             }
         }
 
-        public string WhereInTemplate {
-            get {
+        public string WhereInTemplate
+        {
+            get
+            {
                 return "{0} IN ({1})";
             }
         }
+
+        public string WhereInOrTemplate
+        {
+            get
+            {
+                return "OR";
+            }
+        }
+        public string WhereInAndTemplate
+        {
+            get
+            {
+                return "AND";
+            }
+        }
+        public string WhereInEqualTemplate
+        {
+            get
+            {
+                return "{0}=N'{1}'";
+            }
+        }
+
+        public string WhereInAreaTemplate
+        {
+            get
+            {
+                return "({0})";
+            }
+        }
+
         public virtual string GetTableNameString
         {
             get
@@ -62,7 +95,7 @@ namespace SqlSugar
                 {
                     var isFirst = i == 0;
                     whereString += isFirst ? "WHERE " : "AND ";
-                    whereString +=(item + PubConst.Space);
+                    whereString += (item + PubConst.Space);
                     ++i;
                 }
                 return whereString;
diff --git a/SqlSugar/Abstract/DeleteProvider/DeleteableProvider.cs b/SqlSugar/Abstract/DeleteProvider/DeleteableProvider.cs
index 258382b5a..9562be779 100644
--- a/SqlSugar/Abstract/DeleteProvider/DeleteableProvider.cs
+++ b/SqlSugar/Abstract/DeleteProvider/DeleteableProvider.cs
@@ -22,24 +22,81 @@ namespace SqlSugar
 
         public IDeleteable<T> Where(List<T> deleteObjs)
         {
-            throw new NotImplementedException();
+            if (deleteObjs == null || deleteObjs.Count() == 0)
+            {
+                Where("1=2 ");
+                return this;
+            }
+            string tableName = this.Context.GetTableName<T>();
+            var entityInfo = this.Context.EntityProvider.GetEntityInfo<T>();
+            if (this.Context.IsSystemTablesConfig)
+            {
+                var primaryFields = this.Db.DbMaintenance.GetPrimaries(tableName).ToArray();
+                var isSinglePrimaryKey = primaryFields.Length == 1;
+                Check.ArgumentNullException(primaryFields, string.Format("Table {0} with no primarykey", tableName));
+                if (isSinglePrimaryKey)
+                {
+                    List<object> primaryKeyValues = new List<object>();
+                    var primaryField = primaryFields.Single();
+                    foreach (var deleteObj in deleteObjs)
+                    {
+                        var entityPropertyName = this.Context.GetEntityPropertyName<T>(primaryField);
+                        var columnInfo = entityInfo.Columns.Single(it => it.Name == entityPropertyName);
+                        var value = columnInfo.PropertyInfo.GetValue(deleteObj, null);
+                        primaryKeyValues.Add(value);
+                    }
+                    var inValueString = primaryKeyValues.ToArray().ToJoinSqlInVals();
+                    Where(string.Format(DeleteBuilder.WhereInTemplate, primaryFields.Single(), inValueString));
+                }
+                else
+                {
+                    StringBuilder whereInSql = new StringBuilder();
+                    foreach (var deleteObj in deleteObjs)
+                    {
+                        StringBuilder orString = new StringBuilder();
+                        var isFirst = deleteObjs.IndexOf(deleteObj)==0;
+                        if (isFirst) {
+                            orString.Append(DeleteBuilder.WhereInOrTemplate+PubConst.Space);
+                        }
+                        int i = 0;
+                        StringBuilder andString = new StringBuilder();
+                        foreach (var primaryField in primaryFields)
+                        {
+                            if (i == 0)
+                                andString.Append(DeleteBuilder.WhereInAndTemplate + PubConst.Space);
+                            var entityPropertyName = this.Context.GetEntityPropertyName<T>(primaryField);
+                            var columnInfo = entityInfo.Columns.Single(it => it.Name == entityPropertyName);
+                            var entityValue = columnInfo.PropertyInfo.GetValue(deleteObj, null);
+                            andString.AppendFormat(DeleteBuilder.WhereInEqualTemplate, primaryField, entityValue);
+                            ++i;
+                        }
+                        orString.AppendFormat(DeleteBuilder.WhereInAreaTemplate,andString);
+                        whereInSql.Append(orString);
+                    }
+                    Where(string.Format(DeleteBuilder.WhereInAreaTemplate,whereInSql.ToString()));
+                }
+            }
+            else
+            {
+
+            }
+            return this;
         }
 
         public IDeleteable<T> Where(Expression<Func<T, bool>> expression)
         {
-            var expResult=DeleteBuilder.GetExpressionValue(expression, ResolveExpressType.WhereSingle);
+            var expResult = DeleteBuilder.GetExpressionValue(expression, ResolveExpressType.WhereSingle);
             DeleteBuilder.WhereInfos.Add(expResult.GetResultString());
             return this;
         }
 
         public IDeleteable<T> Where(T deleteObj)
         {
-            string tableName = this.Context.GetTableName<T>();
-
+            Where(new List<T>() { deleteObj });
             return this;
         }
 
-        public IDeleteable<T> Where(string whereString, object whereObj=null)
+        public IDeleteable<T> Where(string whereString, object whereObj = null)
         {
             DeleteBuilder.WhereInfos.Add(whereString);
             if (whereObj != null)
@@ -51,7 +108,8 @@ namespace SqlSugar
 
         public IDeleteable<T> In<PkType>(PkType[] primaryKeyValues)
         {
-            if (primaryKeyValues == null || primaryKeyValues.Count() == 0) {
+            if (primaryKeyValues == null || primaryKeyValues.Count() == 0)
+            {
                 Where("1=2 ");
                 return this;
             }
@@ -63,7 +121,8 @@ namespace SqlSugar
                 Check.ArgumentNullException(primaryField, "Table " + tableName + " with no primarykey");
                 Where(string.Format(DeleteBuilder.WhereInTemplate, primaryField, primaryKeyValues.ToJoinSqlInVals()));
             }
-            else {
+            else
+            {
 
             }
             return this;
@@ -85,7 +144,7 @@ namespace SqlSugar
         {
             string sql = DeleteBuilder.ToSqlString();
             var paramters = DeleteBuilder.Parameters.ToList();
-            return new KeyValuePair<string, List<SugarParameter>>(sql,paramters);
+            return new KeyValuePair<string, List<SugarParameter>>(sql, paramters);
         }
     }
 }
diff --git a/SqlSugar/Common/Check.cs b/SqlSugar/Common/Check.cs
index d61e927ad..bd6a1797d 100644
--- a/SqlSugar/Common/Check.cs
+++ b/SqlSugar/Common/Check.cs
@@ -25,6 +25,11 @@ namespace SqlSugar
             if (checkObj == null)
                 throw new SqlSugarException("SqlSugarException.ArgumentNullException：" + message);
         }
+        public static void ArgumentNullException(object [] checkObj, string message)
+        {
+            if (checkObj == null|| checkObj.Length==0)
+                throw new SqlSugarException("SqlSugarException.ArgumentNullException：" + message);
+        }
 
         public static void Exception(bool isException, string message, params string[] args)
         {
diff --git a/SqlSugar/SqlSugarClient.cs b/SqlSugar/SqlSugarClient.cs
index 931f4e273..5a04cd757 100644
--- a/SqlSugar/SqlSugarClient.cs
+++ b/SqlSugar/SqlSugarClient.cs
@@ -335,7 +335,7 @@ namespace SqlSugar
             else
             {
                 var mappingInfo = this.MappingTables.SingleOrDefault(it => it.EntityName == typeName);
-                return mappingInfo.DbTableName;
+                return mappingInfo==null?typeName:mappingInfo.DbTableName;
             }
         }
         internal string GetEntityName(string tableName)
@@ -344,26 +344,27 @@ namespace SqlSugar
             else
             {
                 var mappingInfo = this.MappingTables.SingleOrDefault(it => it.DbTableName == tableName);
-                return mappingInfo.EntityName;
+                return mappingInfo==null?tableName:mappingInfo.EntityName;
             }
         }
-        internal string GetDbColumnName<T>(string entityNam)
+        internal string GetDbColumnName<T>(string entityPropertyName)
         {
             var typeName = typeof(T).Name;
-            if (this.MappingTables == null || this.MappingTables.Count == 0) return typeName;
+            if (this.MappingColumns == null || this.MappingColumns.Count == 0) return entityPropertyName;
             else
             {
-                var mappingInfo = this.MappingTables.SingleOrDefault(it => it.EntityName == typeName);
-                return mappingInfo.DbTableName;
+                var mappingInfo = this.MappingColumns.SingleOrDefault(it =>it.EntityName==typeName &&it.EntityPropertyName == entityPropertyName);
+                return mappingInfo==null?entityPropertyName:mappingInfo.DbColumnName;
             }
         }
-        internal string GetEntityPropertyName(string bbColumnName)
+        internal string GetEntityPropertyName<T>(string dbColumnName)
         {
-            if (this.MappingTables == null || this.MappingTables.Count == 0) return tableName;
+            var typeName = typeof(T).Name;
+            if (this.MappingColumns == null || this.MappingColumns.Count == 0) return dbColumnName;
             else
             {
-                var mappingInfo = this.MappingTables.SingleOrDefault(it => it.DbTableName == tableName);
-                return mappingInfo.EntityName;
+                var mappingInfo = this.MappingColumns.SingleOrDefault(it => it.EntityName == typeName && it.DbColumnName == dbColumnName);
+                return mappingInfo == null ? dbColumnName : mappingInfo.DbColumnName;
             }
         }
         #endregion