diff --git a/ui/src/workflow/nodes/mcp-node/index.vue b/ui/src/workflow/nodes/mcp-node/index.vue
index ad7717274..3f88b101d 100644
--- a/ui/src/workflow/nodes/mcp-node/index.vue
+++ b/ui/src/workflow/nodes/mcp-node/index.vue
@@ -138,7 +138,7 @@
                   v-model="item.source"
                   size="small"
                   style="width: 85px"
-                  @change="form_data.tool_params[form_data.params_nested] = {}; form_data.tool_params[form_data.params_nested][item.label.label]"
+                  @change="form_data.tool_params[form_data.params_nested] = {}; form_data.tool_params[form_data.params_nested][item.label.label] = ''"
                 >
                   <el-option
                     :label="$t('views.applicationWorkflow.nodes.replyNode.replyContent.reference')"