diff --git a/tests/system-test/2-query/timetruncate.py b/tests/system-test/2-query/timetruncate.py
index ee302a1d8e..ea4f963b71 100644
--- a/tests/system-test/2-query/timetruncate.py
+++ b/tests/system-test/2-query/timetruncate.py
@@ -21,7 +21,6 @@ class TDTestCase:
         self.db_param_precision = ['ms','us','ns']
         self.time_unit = ['1w','1d','1h','1m','1s','1a','1u','1b']
         self.error_unit = ['2w','2d','2h','2m','2s','2a','2u','1c','#1']
-        self.error_unit = ['2w','2d','2h','2m','2s','2a','2u','1c','#1']
         self.ntbname = 'ntb'
         self.stbname = 'stb'
         self.ctbname = 'ctb'