diff --git a/api/core/workflow/nodes/datasource/datasource_node.py b/api/core/workflow/nodes/datasource/datasource_node.py
index 5fb199558d..1ccb062cd5 100644
--- a/api/core/workflow/nodes/datasource/datasource_node.py
+++ b/api/core/workflow/nodes/datasource/datasource_node.py
@@ -43,7 +43,7 @@ class DatasourceNode(Node):
     """
 
     _node_data: DatasourceNodeData
-    _node_type = NodeType.DATASOURCE
+    node_type = NodeType.DATASOURCE
 
     def init_node_data(self, data: Mapping[str, Any]) -> None:
         self._node_data = DatasourceNodeData.model_validate(data)
diff --git a/api/core/workflow/nodes/knowledge_index/knowledge_index_node.py b/api/core/workflow/nodes/knowledge_index/knowledge_index_node.py
index 2880518b94..2efcb69445 100644
--- a/api/core/workflow/nodes/knowledge_index/knowledge_index_node.py
+++ b/api/core/workflow/nodes/knowledge_index/knowledge_index_node.py
@@ -36,7 +36,7 @@ default_retrieval_model = {
 
 class KnowledgeIndexNode(Node):
     _node_data: KnowledgeIndexNodeData
-    _node_type = NodeType.KNOWLEDGE_INDEX
+    node_type = NodeType.KNOWLEDGE_INDEX
 
     def init_node_data(self, data: Mapping[str, Any]) -> None:
         self._node_data = KnowledgeIndexNodeData.model_validate(data)