diff --git a/sheet.ts b/sheet.ts
index a12058c..ca0519e 100644
--- a/sheet.ts
+++ b/sheet.ts
@@ -9,7 +9,7 @@ export default class ShimoSheetCabinet extends CabinetBase {
   private token: string
   private file: ShimoSDK.File
   private editorOptions: ShimoSDK.Sheet.EditorOptions
-  private fetchCollaborators: string
+  private fetchCollaborators: string | ShimoSDK.Sheet.FetchCollaboratorsCallback
   private plugins: string[]
   private collaboration: ShimoSDK.Common.Collaboration
 
@@ -212,7 +212,7 @@ export default class ShimoSheetCabinet extends CabinetBase {
       currentUser: {
         id: this.user.id
       },
-      permission: this.user.permission,
+      permission: this.user.permission!,
       fetchCollaborators: this.fetchCollaborators
     }
     const _ = new this.sdkSheet.plugins.Lock(options)
diff --git a/typings/global.d.ts b/typings/global.d.ts
index 7989181..07722a8 100644
--- a/typings/global.d.ts
+++ b/typings/global.d.ts
@@ -73,6 +73,7 @@ declare global {
       export type ToolbarOptions = IToolbar.ToolbarOptions
       export type Lock = ILock.default
       export type LockOptions = ILock.LockOptions
+      export type FetchCollaboratorsCallback = ILock.FetchCollaboratorsCallback
     }
 
     namespace Document {
diff --git a/typings/sheet/plugins/lock/index.d.ts b/typings/sheet/plugins/lock/index.d.ts
index cc38774..9b543bd 100644
--- a/typings/sheet/plugins/lock/index.d.ts
+++ b/typings/sheet/plugins/lock/index.d.ts
@@ -18,13 +18,15 @@ interface Collaborator {
   displayRole?: string | undefined
 }
 
+export type FetchCollaboratorsCallback = () => Promise<Collaborator[]>
+
 export interface LockOptions {
   editor: Editor
   currentUser: {
     id: number
   }
   permission: PermissionConfig
-  fetchCollaborators: string
+  fetchCollaborators: string | FetchCollaboratorsCallback
 }
 export default class Lock {
   constructor (opts: LockOptions);