diff --git a/pkg/monitor/alerting/conditions/query.go b/pkg/monitor/alerting/conditions/query.go
index 8a6bfcda9f..7fd27cf828 100644
--- a/pkg/monitor/alerting/conditions/query.go
+++ b/pkg/monitor/alerting/conditions/query.go
@@ -663,6 +663,9 @@ func (c *QueryCondition) getFilterResources(start int, end int,
 			continue
 		}
 		relationKey := relationMap[tag.Key]
+		if len(relationKey) == 0 {
+			continue
+		}
 		filterObj := make([]jsonutils.JSONObject, 0)
 		for _, res := range tmp {
 			val, _ := res.GetString(relationKey)