diff --git a/unittest/storage/blocksstable/test_row_reader.cpp b/unittest/storage/blocksstable/test_row_reader.cpp
index 9be31061f6f30a63c5ceb93e05bf78f89ff02b7d..fde7ef2baa259974a802dec90c2e4d2164395f0d 100644
--- a/unittest/storage/blocksstable/test_row_reader.cpp
+++ b/unittest/storage/blocksstable/test_row_reader.cpp
@@ -246,7 +246,7 @@ TEST_F(TestRowReader, test_number_float)
 {
   ObObj write_obj;
   uint32_t digits = 8;
-  write_obj.set_number_float(ObNumber(3, &digits));
+  write_obj.set_number_float(ObNumber(1, &digits));
 
   char* buf = get_serialize_buf();
   int64_t buf_size = 2 * 1024 * 1024;