diff --git a/packages/components/date-picker/src/date-picker-com/panel-date-pick.vue b/packages/components/date-picker/src/date-picker-com/panel-date-pick.vue
index 4d5d9ca600..693dbb62e2 100644
--- a/packages/components/date-picker/src/date-picker-com/panel-date-pick.vue
+++ b/packages/components/date-picker/src/date-picker-com/panel-date-pick.vue
@@ -593,7 +593,7 @@ const isValidValue = (date: unknown) => {
 }
 
 const formatToString = (value: Dayjs | Dayjs[]) => {
-  return Array.isArray(value)
+  return isArray(value)
     ? (value as Dayjs[]).map((_) => _.format(props.format))
     : (value as Dayjs).format(props.format)
 }
diff --git a/packages/components/tree-select/src/tree.ts b/packages/components/tree-select/src/tree.ts
index c41bc66150..a4f1c2fdcb 100644
--- a/packages/components/tree-select/src/tree.ts
+++ b/packages/components/tree-select/src/tree.ts
@@ -17,6 +17,7 @@ import type { Ref } from 'vue'
 import type ElSelect from '@element-plus/components/select'
 import type Node from '@element-plus/components/tree/src/model/node'
 import type { TreeNodeData } from '@element-plus/components/tree/src/tree.type'
+import type { TreeInstance } from '@element-plus/components/tree'
 
 export const useTree = (
   props,
@@ -27,7 +28,7 @@ export const useTree = (
     key,
   }: {
     select: Ref<InstanceType<typeof ElSelect> | undefined>
-    tree: Ref<InstanceType<typeof ElTree> | undefined>
+    tree: Ref<TreeInstance | undefined>
     key: Ref<string>
   }
 ) => {
@@ -208,9 +209,7 @@ export const useTree = (
         if (props.multiple) {
           emit(
             UPDATE_MODEL_EVENT,
-            cachedKeys.concat(
-              (tree.value as InstanceType<typeof ElTree>).getCheckedKeys(true)
-            )
+            cachedKeys.concat((tree.value as TreeInstance).getCheckedKeys(true))
           )
         } else {
           // select first leaf node when check parent