diff --git a/source/common/src/ttime.c b/source/common/src/ttime.c
index 023a425df2..376cfce255 100644
--- a/source/common/src/ttime.c
+++ b/source/common/src/ttime.c
@@ -872,18 +872,17 @@ int64_t taosTimeTruncate(int64_t ts, const SInterval* pInterval) {
   ASSERT(pInterval->offset >= 0);
 
   if (pInterval->offset > 0) {
-    start = taosTimeAdd(start, pInterval->offset, pInterval->offsetUnit, precision);
-
     // try to move current window to the left-hande-side, due to the offset effect.
     int64_t end = taosTimeAdd(start, pInterval->interval, pInterval->intervalUnit, precision) - 1;
-
     int64_t newe = end;
+    int64_t slidingEnd = end;
     while (newe >= ts) {
-      end = newe;
-      newe = taosTimeAdd(newe, -pInterval->sliding, pInterval->slidingUnit, precision);
+      end = slidingEnd;
+      slidingEnd = taosTimeAdd(slidingEnd, -pInterval->sliding, pInterval->slidingUnit, precision);
+      newe = taosTimeAdd(slidingEnd, pInterval->offset, pInterval->offsetUnit, precision);
     }
-
-    start = taosTimeAdd(end, -pInterval->interval, pInterval->intervalUnit, precision) + 1;
+    int64_t slidingStart = taosTimeAdd(end, -pInterval->interval, pInterval->intervalUnit, precision) + 1;
+    start = taosTimeAdd(slidingStart, pInterval->offset, pInterval->offsetUnit, precision);
   }
 
   return start;
diff --git a/source/libs/executor/test/timewindowTest.cpp b/source/libs/executor/test/timewindowTest.cpp
index 2894c66587..7a83b64fac 100644
--- a/source/libs/executor/test/timewindowTest.cpp
+++ b/source/libs/executor/test/timewindowTest.cpp
@@ -158,4 +158,27 @@ TEST(testCase, timewindow_gen) {
 
 }
 
+TEST(testCase, timewindow_natural) {
+  osSetTimezone("CST");
+
+  int32_t precision = TSDB_TIME_PRECISION_MILLI;
+
+  SInterval interval2 = createInterval(17, 17, 13392000000, 'n', 'n', 0, precision);
+  int64_t key1 = 1633446027072;
+  STimeWindow w1 = {0};
+  getInitialStartTimeWindow(&interval2, key1, &w1, true);
+  printTimeWindow(&w1, precision, key1);
+  STimeWindow w3 = getAlignQueryTimeWindow(&interval2, key1);
+  printf("%ld win %ld, %ld\n", key1, w3.skey, w3.ekey);  
+
+  int64_t key2 = 1648758398208;
+  STimeWindow w2 = {0};
+  getInitialStartTimeWindow(&interval2, key2, &w2, true);
+  printTimeWindow(&w2, precision, key2);
+  STimeWindow w4 = getAlignQueryTimeWindow(&interval2, key2);
+  printf("%ld win %ld, %ld\n", key2, w3.skey, w3.ekey);
+
+  ASSERT_EQ(w3.skey, w4.skey);
+  ASSERT_EQ(w3.ekey, w4.ekey);  
+}
 #pragma GCC diagnostic pop
\ No newline at end of file
diff --git a/tests/parallel_test/cases.task b/tests/parallel_test/cases.task
index 3db6eccffc..752234bbf5 100644
--- a/tests/parallel_test/cases.task
+++ b/tests/parallel_test/cases.task
@@ -36,6 +36,7 @@
 #,,n,system-test,python3 ./test.py -f 8-stream/snode_restart_with_checkpoint.py -N 4
 
 ,,y,system-test,./pytest.sh python3 ./test.py -f 2-query/tbname_vgroup.py
+,,y,system-test,./pytest.sh python3 ./test.py -f 2-query/count_interval.py
 ,,y,system-test,./pytest.sh python3 ./test.py -f 2-query/compact-col.py
 ,,y,system-test,./pytest.sh python3 ./test.py -f 2-query/stbJoin.py
 ,,y,system-test,./pytest.sh python3 ./test.py -f 2-query/stbJoin.py -Q 2
diff --git a/tests/system-test/2-query/count_interval.py b/tests/system-test/2-query/count_interval.py
new file mode 100644
index 0000000000..b37cc1db22
--- /dev/null
+++ b/tests/system-test/2-query/count_interval.py
@@ -0,0 +1,60 @@
+###################################################################
+#           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 sys
+import taos
+from util.log import tdLog
+from util.cases import tdCases
+from util.sql import tdSql
+from util.dnodes import tdDnodes
+import random
+
+
+class TDTestCase:
+    def init(self, conn, logSql, replicaVar=1):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor(), logSql)
+        
+    def restartTaosd(self, index=1, dbname="db"):
+        tdDnodes.stop(index)
+        tdDnodes.startWithoutSleep(index)
+        tdSql.execute(f"use d")
+        
+    def run(self):
+        tdSql.execute("drop database if exists d");
+        tdSql.execute("create database d");
+        tdSql.execute("use d");
+        tdSql.execute("create table st(ts timestamp, f int) tags (t int)")
+        
+        for i in range(-2048, 2047):
+            ts = 1626624000000 + i;
+            tdSql.execute(f"insert into ct1 using st tags(1) values({ts}, {i})")
+            
+        tdSql.execute("flush database d")
+        for i in range(1638):
+            ts = 1648758398208 + i
+            tdSql.execute(f"insert into ct1 using st tags(1) values({ts}, {i})")
+        tdSql.execute("insert into ct1 using st tags(1) values(1648970742528, 1638)")
+        tdSql.execute("flush database d")
+        
+        tdSql.query("select count(ts) from ct1 interval(17n, 5n)")           
+        self.restartTaosd()
+        tdSql.query("select count(ts) from ct1 interval(17n, 5n)")           
+
+    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