diff --git a/tests/parallel_test/cases.task b/tests/parallel_test/cases.task
index d26c1e21814b727941052a96a1d417f9f9fdb8a7..7e58ea9a13d8a0b7cd56d274269aacb738f589ac 100644
--- a/tests/parallel_test/cases.task
+++ b/tests/parallel_test/cases.task
@@ -143,6 +143,7 @@
 ,,n,system-test,python3 ./test.py -f 0-others/udfpy_main.py
 ,,n,system-test,python3 ./test.py -N 3 -f 0-others/walRetention.py
 ,,y,system-test,./pytest.sh python3 ./test.py -f 1-insert/alter_database.py
+,,y,system-test,./pytest.sh python3 ./test.py -f 1-insert/alter_replica.py -N 3
 ,,y,system-test,./pytest.sh python3 ./test.py -f 1-insert/influxdb_line_taosc_insert.py
 ,,y,system-test,./pytest.sh python3 ./test.py -f 1-insert/opentsdb_telnet_line_taosc_insert.py
 ,,y,system-test,./pytest.sh python3 ./test.py -f 1-insert/opentsdb_json_taosc_insert.py
diff --git a/tests/system-test/1-insert/alter_replica.py b/tests/system-test/1-insert/alter_replica.py
new file mode 100644
index 0000000000000000000000000000000000000000..900b64d9433ce3f0ec9b971926019c84f669744d
--- /dev/null
+++ b/tests/system-test/1-insert/alter_replica.py
@@ -0,0 +1,114 @@
+import taos
+import sys
+import time
+import socket
+import os
+import threading
+import datetime
+
+from util.log import *
+from util.sql import *
+from util.cases import *
+from util.dnodes import *
+
+
+class TDTestCase:
+    def init(self, conn, logSql, replicaVar=1):
+        self.replicaVar = int(replicaVar)
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor(), logSql)        
+        
+    def checkVgroups(self, dbName, vgNum):
+        sleepNum = vgNum * 60
+        flag = 0
+        while (sleepNum > 0):
+            sql = f'show {dbName}.vgroups'
+            tdSql.query(sql)
+            flag = 0
+            for vgid in range (vgNum) :
+                v1_status = tdSql.queryResult[vgid][4]
+                v2_status = tdSql.queryResult[vgid][6]
+                v3_status = tdSql.queryResult[vgid][8]
+                if ((v1_status == 'leader') and (v2_status == 'follower') and (v3_status == 'follower')) \
+                or ((v2_status == 'leader') and (v1_status == 'follower') and (v3_status == 'follower')) \
+                or ((v3_status == 'leader') and (v2_status == 'follower') and (v1_status == 'follower')):
+                    continue
+                else: 
+                    sleepNum = sleepNum - 1
+                    time.sleep(1)
+                    flag = 1
+                    break
+            if (0 == flag):
+                return 0
+        tdLog.debug("vgroup[%d] status: %s, %s, %s" %(vgid,v1_status,v2_status,v3_status))
+        return -1
+        
+    def alter_replica(self):        
+        # create db and alter replica
+        tdLog.debug("====alter db repica 1====")
+        vgNum = 3
+        dbName = 'db1'
+        sql = f'create database {dbName} vgroups {vgNum}'
+        tdSql.execute(sql)
+        sql = f'alter database {dbName} replica 3'
+        tdSql.execute(sql)
+        tdLog.debug("start check time: %s"%(str(datetime.datetime.now())))
+        res = self.checkVgroups(dbName, vgNum)       
+        tdLog.debug("end   check time: %s"%(str(datetime.datetime.now())))
+        if (0 != res):
+            tdLog.exit(f'fail: alter database {dbName} replica 3') 
+        
+        # create db, stable, child tables, and insert data, then alter replica
+        tdLog.debug("====alter db repica 2====")
+        dbName = 'db2'
+        sql = f'create database {dbName} vgroups {vgNum}'
+        tdSql.execute(sql)        
+        sql = f'use {dbName}'
+        tdSql.execute(sql)
+        sql = f'create stable stb (ts timestamp, c int) tags (t int)'
+        tdSql.execute(sql)
+        sql = f'create table ctb using stb tags (1)'
+        tdSql.execute(sql)
+        sql = f'insert into ctb values (now, 1) (now+1s, 2) (now+2s, 3)'
+        tdSql.execute(sql)
+        sql = f'alter database {dbName} replica 3'
+        tdSql.execute(sql)
+        tdLog.debug("start check time: %s"%(str(datetime.datetime.now())))
+        res = self.checkVgroups(dbName, vgNum)
+        tdLog.debug("end   check time: %s"%(str(datetime.datetime.now())))
+        if (0 != res):
+            tdLog.exit(f'fail: alter database {dbName} replica 3')        
+        
+        # firstly create db, stable, child tables, and insert data, then drop stable, and then alter replica
+        tdLog.debug("====alter db repica 3====")
+        dbName = 'db3'
+        sql = f'create database {dbName} vgroups {vgNum}'
+        tdSql.execute(sql)
+        sql = f'use {dbName}'
+        tdSql.execute(sql)
+        sql = f'create stable stb (ts timestamp, c int) tags (t int)'
+        tdSql.execute(sql)
+        sql = f'create table ctb using stb tags (1)'
+        tdSql.execute(sql)
+        sql = f'insert into ctb values (now, 1) (now+1s, 2) (now+2s, 3)'
+        tdSql.execute(sql)      
+        sql = f'drop table stb'
+        tdSql.execute(sql)        
+        sql = f'alter database {dbName} replica 3'
+        tdSql.execute(sql)
+        tdLog.debug("start check time: %s"%(str(datetime.datetime.now())))
+        res = self.checkVgroups(dbName, vgNum)
+        tdLog.debug("end   check time: %s"%(str(datetime.datetime.now())))
+        if (0 != res):
+            tdLog.exit(f'fail: alter database {dbName} replica 3')
+
+    def run(self):
+        self.alter_replica()
+
+    def stop(self):
+        tdSql.close()
+        tdLog.success(f"{__file__} successfully executed")
+
+
+tdCases.addLinux(__file__, TDTestCase())
+tdCases.addWindows(__file__, TDTestCase())