diff --git a/log/format.go b/log/format.go
index 584af0ad..6fb91d31 100644
--- a/log/format.go
+++ b/log/format.go
@@ -78,7 +78,7 @@ func (f Formatter) Format(ctx context.Context, level Level, tag string, message
 		message = levelString + "[" + xd(int(timestamp.Sub(f.BaseTime)/time.Second), 4) + "] " + message
 	}
 	if f.DisableLineBreak {
-		if message[len(message)-1] != '\n' {
+		if message[len(message)-1] == '\n' {
 			message = message[:len(message)-1]
 		}
 	} else {