diff --git a/bsp/stm32f107/rtconfig.h b/bsp/stm32f107/rtconfig.h
index f6e28a521a..c4cd0c8368 100644
--- a/bsp/stm32f107/rtconfig.h
+++ b/bsp/stm32f107/rtconfig.h
@@ -163,4 +163,5 @@
 // <bool name="RT_USING_BSP_CMSIS" description="Using CMSIS in BSP" default="true" />
 // #define RT_USING_BSP_CMSIS
 
+#define RT_USING_LIBC
 #endif