diff --git a/bin/csh/config.h b/bin/csh/config.h
index 7de7af6f423..23a25859c19 100644
--- a/bin/csh/config.h
+++ b/bin/csh/config.h
@@ -156,7 +156,6 @@
 #ifdef WANT_KANJI
 #define KANJI
 #define DSPMBYTE
-#define MBYTEDEBUG
 #endif
 
 #endif /* _h_config */
diff --git a/bin/csh/config_p.h b/bin/csh/config_p.h
index 7de7af6f423..23a25859c19 100644
--- a/bin/csh/config_p.h
+++ b/bin/csh/config_p.h
@@ -156,7 +156,6 @@
 #ifdef WANT_KANJI
 #define KANJI
 #define DSPMBYTE
-#define MBYTEDEBUG
 #endif
 
 #endif /* _h_config */