diff --git a/frontend/src/views/dataset/data/UnionView.vue b/frontend/src/views/dataset/data/UnionView.vue
index fcc08d37e2..b2a09cc388 100644
--- a/frontend/src/views/dataset/data/UnionView.vue
+++ b/frontend/src/views/dataset/data/UnionView.vue
@@ -270,6 +270,7 @@ export default {
         targetUnionRelation: ''
       }
       this.targetTable = {}
+      this.targetFieldOption = []
     },
 
     edit(item) {