diff --git a/models/repo_list.go b/models/repo_list.go
index 928e1f9532..c4d8ee8237 100755
--- a/models/repo_list.go
+++ b/models/repo_list.go
@@ -331,7 +331,7 @@ func SearchRepositoryCondition(opts *SearchRepoOptions) builder.Cond {
 	}
 	if opts.TopicName != "" {
 		var subQueryCond = builder.NewCond()
-		subQueryCond = subQueryCond.Or(builder.Eq{"topic.name": opts.TopicName})
+		subQueryCond = subQueryCond.Or(builder.Eq{"topic.name": strings.ToLower(opts.TopicName)})
 		subQuery := builder.Select("repo_topic.repo_id").From("repo_topic").
 			Join("INNER", "topic", "topic.id = repo_topic.topic_id").
 			Where(subQueryCond).