diff --git a/src/idle.c b/src/idle.c
index 49466b81b4e34dcad634d75bed36abcd8f41d387..2c5d929111e70a6b241988a76c85360fc5586039 100644
--- a/src/idle.c
+++ b/src/idle.c
@@ -17,11 +17,13 @@
 #include <rtthread.h>
 #include "kservice.h"
 
+#ifndef IDLE_THREAD_STACK_SIZE
 #if defined (RT_USING_HOOK) || defined(RT_USING_HEAP)
 #define IDLE_THREAD_STACK_SIZE	256
 #else
 #define IDLE_THREAD_STACK_SIZE	128
 #endif
+#endif
 
 static struct rt_thread idle;
 ALIGN(RT_ALIGN_SIZE)