diff --git a/scripts/image b/scripts/image
index e2b557c7b2..10e1835518 100755
--- a/scripts/image
+++ b/scripts/image
@@ -64,7 +64,7 @@ if [ "$PROJECT" == "imx6" -a -n "$SYSTEM" ]; then
   IMAGE_NAME="$IMAGE_NAME-$SYSTEM"
 fi
 
-if [ ! -z "$CUSTOM_IMAGE_NAME" ]; then
+if [ -n "$CUSTOM_IMAGE_NAME" ]; then
    IMAGE_NAME="$CUSTOM_IMAGE_NAME" 
 fi