diff --git a/ipc/native/test/unittest/common/ipc_hitrace_unittest.cpp b/ipc/native/test/unittest/common/ipc_hitrace_unittest.cpp
index cb11976ffa17c98351615d19f177a14b6f534155..49a3d2c4a5e25a8fea33dcdf0ff3f02199acc620 100644
--- a/ipc/native/test/unittest/common/ipc_hitrace_unittest.cpp
+++ b/ipc/native/test/unittest/common/ipc_hitrace_unittest.cpp
@@ -72,7 +72,7 @@ void BinderTraceTest::TearDownTestCase()
 static std::string HitraceLongToString(unsigned long data)
 {
     std::string result;
-    constexpr int BUFFER_SIZE = 16;
+    constexpr int BUFFER_SIZE = 21;
     char str[BUFFER_SIZE] = {0};
 
     if (sprintf_s(str, sizeof(str), "%lu", data) <= 0) {