diff --git a/include/config.h b/include/config.h
index 8c80515d..1792d79f 100644
--- a/include/config.h
+++ b/include/config.h
@@ -2,9 +2,6 @@
  * See Copyright Notice in picrin.h
  */
 
-#ifndef CONFIG_H__
-#define CONFIG_H__
-
 /** switch normal VM and direct threaded VM */
 /* #define PIC_DIRECT_THREADED_VM 1 */
 
@@ -107,5 +104,3 @@
 # define GC_DEBUG 0
 # define GC_DEBUG_DETAIL 0
 #endif
-
-#endif