diff --git a/web/app/components/workflow/nodes/_base/components/form-input-item.tsx b/web/app/components/workflow/nodes/_base/components/form-input-item.tsx
index c4c3221d09..98dfc261e5 100644
--- a/web/app/components/workflow/nodes/_base/components/form-input-item.tsx
+++ b/web/app/components/workflow/nodes/_base/components/form-input-item.tsx
@@ -64,7 +64,7 @@ const FormInputItem: FC<Props> = ({
   const isFile = type === FormTypeEnum.file || type === FormTypeEnum.files
   const showTypeSwitch = isNumber || isObject || isArray
   const isVariable = varInput?.type === VarKindType.variable
-  const isConstant = varInput?.type === VarKindType.constant
+  const isConstant = varInput?.type === VarKindType.constant || !varInput?.type
 
   const { availableVars, availableNodesWithParent } = useAvailableVarList(nodeId, {
     onlyLeafNodeVar: false,