diff --git a/bird/parser.go b/bird/parser.go
index 9f000b3..0de6b1a 100644
--- a/bird/parser.go
+++ b/bird/parser.go
@@ -130,7 +130,7 @@ func mainRouteDetail(groups []string, route Parsed) Parsed {
 	route["metric"] = parseInt(groups[8])
 
 	for k, _ := range route {
-		if !dirtyContains(ParserConf.FilterFields, k) {
+		if dirtyContains(ParserConf.FilterFields, k) {
 			route[k] = nil
 		}
 	}