diff --git a/packages/angular-query-experimental/src/__tests__/query-options.test-d.ts b/packages/angular-query-experimental/src/__tests__/query-options.test-d.ts
index 4afe19c2af..5ec64e83bb 100644
--- a/packages/angular-query-experimental/src/__tests__/query-options.test-d.ts
+++ b/packages/angular-query-experimental/src/__tests__/query-options.test-d.ts
@@ -25,6 +25,25 @@ describe('queryOptions', () => {
       },
     })
   })
+
+  test('should allow undefined response in initialData', () => {
+    return (id: string | null) =>
+      queryOptions({
+        queryKey: ['todo', id],
+        queryFn: () =>
+          Promise.resolve({
+            id: '1',
+            title: 'Do Laundry',
+          }),
+        initialData: () =>
+          !id
+            ? undefined
+            : {
+                id,
+                title: 'Initial Data',
+              },
+      })
+  })
 })
 
 test('should work when passed to injectQuery', () => {
diff --git a/packages/angular-query-experimental/src/query-options.ts b/packages/angular-query-experimental/src/query-options.ts
index 7e958f3df7..519ff4b20a 100644
--- a/packages/angular-query-experimental/src/query-options.ts
+++ b/packages/angular-query-experimental/src/query-options.ts
@@ -1,4 +1,9 @@
-import type { DataTag, DefaultError, QueryKey } from '@tanstack/query-core'
+import {
+  DataTag,
+  DefaultError,
+  QueryKey,
+  InitialDataFunction,
+} from '@tanstack/query-core'
 import type { CreateQueryOptions } from './types'
 
 export type UndefinedInitialDataOptions<
@@ -20,7 +25,7 @@ export type DefinedInitialDataOptions<
 > = CreateQueryOptions<TQueryFnData, TError, TData, TQueryKey> & {
   initialData:
     | NonUndefinedGuard<TQueryFnData>
-    | (() => NonUndefinedGuard<TQueryFnData>)
+    | InitialDataFunction<NonUndefinedGuard<TQueryFnData>>
 }
 
 export function queryOptions<