diff --git a/README.md b/README.md
index a44b4bb1..211e4124 100644
--- a/README.md
+++ b/README.md
@@ -181,7 +181,7 @@ There is a chat room on chat.freenode.org, channel #picrin.
 
         $ make
 
-	If you are building picrin on other systems than x86_64, PIC_NAN_BOXING flag is automatically turned on (see include/config.h for detail).
+	If you are building picrin on other systems than x86_64, PIC_NAN_BOXING flag is automatically turned on (see include/picrin/config.h for detail).
 
 - install
 
diff --git a/include/picrin.h b/include/picrin.h
index 7f44c8e2..bac8032b 100644
--- a/include/picrin.h
+++ b/include/picrin.h
@@ -41,7 +41,7 @@ extern "C" {
 #include "xfile/xfile.h"
 #include "xrope/xrope.h"
 
-#include "config.h"
+#include "picrin/config.h"
 #include "picrin/util.h"
 #include "picrin/value.h"
 
diff --git a/include/config.h b/include/picrin/config.h
similarity index 100%
rename from include/config.h
rename to include/picrin/config.h