diff --git a/include/rtthread.h b/include/rtthread.h
index ccd2d147a8..980c4771b3 100644
--- a/include/rtthread.h
+++ b/include/rtthread.h
@@ -522,7 +522,6 @@ rt_int32_t rt_vsprintf(char *dest, const char *format, va_list arg_ptr);
 rt_int32_t rt_vsnprintf(char *buf, rt_size_t size, const char *fmt, va_list args);
 rt_int32_t rt_sprintf(char *buf, const char *format, ...);
 rt_int32_t rt_snprintf(char *buf, rt_size_t size, const char *format, ...);
-rt_int32_t rt_sscanf(const char *buf, const char *fmt, ...);
 
 #if defined(RT_USING_DEVICE) && defined(RT_USING_CONSOLE)
 rt_device_t rt_console_set_device(const char *name);