diff --git a/src/val_str.c b/src/val_str.c
index a0faf3e..59c34f3 100644
--- a/src/val_str.c
+++ b/src/val_str.c
@@ -1,8 +1,6 @@
 #include <string.h>
 #include <limits.h>
 #include "ucore/val_str.h"
-#include "ucore/saturating_math.h"
-
 
 const char *uc_val_2_str(unsigned int val, const struct UCValStr *array)
 {