diff --git a/include/cos_defines.h b/include/cos_defines.h
index 30035f8..be7aa55 100644
--- a/include/cos_defines.h
+++ b/include/cos_defines.h
@@ -78,8 +78,8 @@ typedef enum cos_log_level {
 #define SDK_LOG_ERR(fmt, ...)           COS_LOW_LOGPRN(COS_LOG_ERR,  fmt, ##__VA_ARGS__, "")
 #define SDK_LOG_COS(level, fmt, ...)    COS_LOW_LOGPRN(level,  fmt, ##__VA_ARGS__, "")
 
-#define MIN(a, b) ((a) < (b) ? (a) : (b))
-#define MAX(a, b) ((a) > (b) ? (a) : (b))
+#define MIN(a,b) (((a)<(b))?(a):(b))
+#define MAX(a,b) (((a)>(b))?(a):(b))
 
 struct Content {
     std::string m_key; // Object 的 Key