diff --git a/src/nm-serial-device.c b/src/nm-serial-device.c
index 127b6bb11d..db8dc7be60 100644
--- a/src/nm-serial-device.c
+++ b/src/nm-serial-device.c
@@ -21,7 +21,7 @@
 #include "nm-utils.h"
 #include "nm-serial-device-glue.h"
 
-#define NM_DEBUG_SERIAL 1
+/* #define NM_DEBUG_SERIAL 1 */
 
 #define SERIAL_BUF_SIZE 2048