diff --git a/routers/web/repo/pull.go b/routers/web/repo/pull.go
index 43ddc265cfafb..012c75983e17b 100644
--- a/routers/web/repo/pull.go
+++ b/routers/web/repo/pull.go
@@ -1109,8 +1109,9 @@ func MergePullRequest(ctx *context.Context) {
 	}
 
 	form.MergeMessageField = strings.TrimSpace(form.MergeMessageField)
+	message += "\n"
 	if len(form.MergeMessageField) > 0 {
-		message += "\n\n" + form.MergeMessageField
+		message += "\n" + form.MergeMessageField
 	}
 
 	if form.MergeWhenChecksSucceed {