diff --git a/webapp/packages/supersonic-fe/src/pages/SemanticModel/Datasource/components/DataSourceCreateForm.tsx b/webapp/packages/supersonic-fe/src/pages/SemanticModel/Datasource/components/DataSourceCreateForm.tsx
index 3669195ac..504a19997 100644
--- a/webapp/packages/supersonic-fe/src/pages/SemanticModel/Datasource/components/DataSourceCreateForm.tsx
+++ b/webapp/packages/supersonic-fe/src/pages/SemanticModel/Datasource/components/DataSourceCreateForm.tsx
@@ -119,7 +119,7 @@ const ModelCreateForm: React.FC<CreateFormProps> = ({
               dateFormat,
               typeParams: {
                 isPrimary: true,
-                timeGranularity,
+                timeGranularity: timeGranularity || '',
               },
             });
             break;
diff --git a/webapp/packages/supersonic-fe/src/pages/SemanticModel/Datasource/components/DataSourceFieldForm.tsx b/webapp/packages/supersonic-fe/src/pages/SemanticModel/Datasource/components/DataSourceFieldForm.tsx
index 281b9de5b..41d1404f2 100644
--- a/webapp/packages/supersonic-fe/src/pages/SemanticModel/Datasource/components/DataSourceFieldForm.tsx
+++ b/webapp/packages/supersonic-fe/src/pages/SemanticModel/Datasource/components/DataSourceFieldForm.tsx
@@ -211,12 +211,13 @@ const FieldForm: React.FC<Props> = ({ fields, sql, onFieldChange, onSqlChange })
               <span>时间粒度:</span>
               <Select
                 placeholder="时间粒度"
-                value={timeGranularity}
+                value={timeGranularity === '' ? undefined : timeGranularity}
                 onChange={(value) => {
                   handleFieldChange(record, 'timeGranularity', value);
                 }}
-                defaultValue={DATE_OPTIONS[0]}
-                style={{ minWidth: 50 }}
+                defaultValue={timeGranularity === '' ? undefined : DATE_OPTIONS[0]}
+                style={{ minWidth: 80 }}
+                allowClear
               >
                 {DATE_OPTIONS.map((item) => (
                   <Option key={item} value={item}>