diff --git a/tests/pytest/fulltest.sh b/tests/pytest/fulltest.sh
index fdcd0a3c42c95039e15743460d170e5f72d9f60d..17c2fc6915f7a5386992b16713fa6279d521f443 100755
--- a/tests/pytest/fulltest.sh
+++ b/tests/pytest/fulltest.sh
@@ -381,6 +381,7 @@ python3 test.py -f  alter/alter_create_exception.py
 python3 ./test.py -f insert/flushwhiledrop.py
 python3 ./test.py -f insert/schemalessInsert.py
 python3 ./test.py -f alter/alterColMultiTimes.py 
+python3 ./test.py -f query/queryTbnameUpperLower.py 
 
 #======================p4-end===============
 
diff --git a/tests/pytest/query/queryTbnameUpperLower.py b/tests/pytest/query/queryTbnameUpperLower.py
new file mode 100644
index 0000000000000000000000000000000000000000..bd4e85c5ca61628093348f520b6e6a04bef07f4a
--- /dev/null
+++ b/tests/pytest/query/queryTbnameUpperLower.py
@@ -0,0 +1,78 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+from util.log import tdLog
+from util.cases import tdCases
+from util.sql import tdSql
+from util.common import tdCom
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor(), logSql)
+
+    def checkStbWhereIn(self):
+        '''
+            where in ---> upper lower mixed
+        '''
+        tdCom.cleanTb()
+        table_name = tdCom.getLongName(8, "letters_mixed")
+        table_name_sub = f'{table_name}_sub'
+        tb_name_lower = table_name_sub.lower()
+        tb_name_upper = table_name_sub.upper()
+
+        ## create stb and tb
+        tdSql.execute(f'CREATE TABLE {table_name} (ts timestamp, id int, bi1 binary(20)) tags (si1 binary(20))')
+        tdSql.execute(f'create table {table_name_sub}1 using {table_name} tags ("{table_name_sub}1")')
+        tdSql.execute(f'create table {tb_name_lower}2 using {table_name} tags ("{tb_name_lower}2")')
+        tdSql.execute(f'create table {tb_name_upper}3 using {table_name} tags ("{tb_name_upper}3")')
+
+        ## insert values
+        tdSql.execute(f'insert into {table_name_sub}1 values (now-1s, 1, "{table_name_sub}1")')
+        tdSql.execute(f'insert into {tb_name_lower}2 values (now-2s, 2, "{tb_name_lower}21")')
+        tdSql.execute(f'insert into {tb_name_lower}2 values (now-3s, 3, "{tb_name_lower}22")')
+        tdSql.execute(f'insert into {tb_name_upper}3 values (now-4s, 4, "{tb_name_upper}31")')
+        tdSql.execute(f'insert into {tb_name_upper}3 values (now-5s, 5, "{tb_name_upper}32")')
+        tdSql.execute(f'insert into {tb_name_upper}3 values (now-6s, 6, "{tb_name_upper}33")')
+
+        ## query where tbname in single
+        tdSql.query(f'select * from {table_name} where tbname in ("{table_name_sub}1")')
+        tdSql.checkRows(1)
+        tdSql.query(f'select * from {table_name} where tbname in ("{table_name_sub.upper()}1")')
+        tdSql.checkRows(1)
+        tdSql.query(f'select * from {table_name} where tbname in ("{table_name_sub.lower()}1")')
+        tdSql.checkRows(1)
+        tdSql.query(f'select * from {table_name} where tbname in ("{tb_name_lower}2")')
+        tdSql.checkRows(2)
+        tdSql.query(f'select * from {table_name} where tbname in ("{tb_name_lower.upper()}2")')
+        tdSql.checkRows(2)
+        tdSql.query(f'select * from {table_name} where tbname in ("{tb_name_upper}3")')
+        tdSql.checkRows(3)
+        tdSql.query(f'select * from {table_name} where tbname in ("{tb_name_upper.lower()}3")')
+        tdSql.checkRows(3)
+        
+        ## query where tbname in multi
+        tdSql.query(f'select * from {table_name} where id=5 and tbname in ("{table_name_sub}1", "{tb_name_lower.upper()}2", "{tb_name_upper.lower()}3")')
+        tdSql.checkRows(1)
+        tdSql.query(f'select * from {table_name} where tbname in ("{table_name_sub}1", "{tb_name_lower.upper()}2", "{tb_name_upper.lower()}3")')
+        tdSql.checkRows(6)
+
+    def run(self):
+        tdSql.prepare()
+        self.checkStbWhereIn()
+
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
\ No newline at end of file
diff --git a/tests/pytest/util/common.py b/tests/pytest/util/common.py
new file mode 100644
index 0000000000000000000000000000000000000000..1c7d94a8a4c8cd454d41c6d4d4d89b8377ec88b7
--- /dev/null
+++ b/tests/pytest/util/common.py
@@ -0,0 +1,53 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import random
+import string
+from util.sql import tdSql
+
+class TDCom:
+    def init(self, conn, logSql):
+        tdSql.init(conn.cursor(), logSql)
+
+    def cleanTb(self):
+        query_sql = "show stables"
+        res_row_list = tdSql.query(query_sql, True)
+        stb_list = map(lambda x: x[0], res_row_list)
+        for stb in stb_list:
+            tdSql.execute(f'drop table if exists {stb}')
+
+        query_sql = "show tables"
+        res_row_list = tdSql.query(query_sql, True)
+        tb_list = map(lambda x: x[0], res_row_list)
+        for tb in tb_list:
+            tdSql.execute(f'drop table if exists {tb}')
+
+    def getLongName(self, len, mode = "mixed"):
+        """
+            generate long name
+            mode could be numbers/letters/letters_mixed/mixed
+        """    
+        if mode == "numbers": 
+            chars = ''.join(random.choice(string.digits) for i in range(len))
+        elif mode == "letters": 
+            chars = ''.join(random.choice(string.ascii_letters.lower()) for i in range(len))
+        elif mode == "letters_mixed": 
+            chars = ''.join(random.choice(string.ascii_letters.upper() + string.ascii_letters.lower()) for i in range(len))
+        else:
+            chars = ''.join(random.choice(string.ascii_letters.lower() + string.digits) for i in range(len))
+        return chars
+
+    def close(self):
+        self.cursor.close()
+
+tdCom = TDCom()
\ No newline at end of file