diff --git a/src/__tests__/alert.test.js b/src/__tests__/alert.test.js
index 797ff86..c4355b9 100644
--- a/src/__tests__/alert.test.js
+++ b/src/__tests__/alert.test.js
@@ -55,6 +55,29 @@ describe('triggers callbacks', () => {
     expect(onOk).toHaveBeenCalled();
   });
 
+  it('works with async onOk function', async () => {
+    const asyncOnOk = jest.fn(
+      () =>
+        new Promise((resolve) => {
+          setTimeout(() => {
+            resolve();
+          }, 1000);
+        })
+    );
+    const promise = alert('Message', {
+      async onOk() {
+        await asyncOnOk();
+      },
+    });
+
+    const okButton = screen.getByRole('button', { name: '确定' });
+    userEvent.click(okButton);
+
+    expect(asyncOnOk).toHaveBeenCalled();
+
+    await act(() => promise);
+  });
+
   describe('waits for async onOk', () => {
     let promise;
     beforeEach(async () => {
diff --git a/src/__tests__/confirm.test.js b/src/__tests__/confirm.test.js
index 259814b..fc90e71 100644
--- a/src/__tests__/confirm.test.js
+++ b/src/__tests__/confirm.test.js
@@ -97,6 +97,29 @@ describe('triggers callbacks', () => {
     expect(onCancel).toHaveBeenCalled();
   });
 
+  it('works with async onOk function', async () => {
+    const asyncOnOk = jest.fn(
+      () =>
+        new Promise((resolve) => {
+          setTimeout(() => {
+            resolve();
+          }, 1000);
+        })
+    );
+    const promise = confirm('Message', {
+      async onOk() {
+        await asyncOnOk();
+      },
+    });
+
+    const okButton = screen.getByRole('button', { name: '确定' });
+    userEvent.click(okButton);
+
+    expect(asyncOnOk).toHaveBeenCalled();
+
+    await act(() => promise);
+  });
+
   describe('waits for async onOk', () => {
     it('shows loading on ok button', async () => {
       const asyncOnOk = jest.fn(
diff --git a/src/__tests__/prompt.test.js b/src/__tests__/prompt.test.js
index d7b3181..ed7a5f5 100644
--- a/src/__tests__/prompt.test.js
+++ b/src/__tests__/prompt.test.js
@@ -139,6 +139,29 @@ describe('triggers callbacks', () => {
     expect(onCancel).toHaveBeenCalled();
   });
 
+  it('works with async onOk function', async () => {
+    const asyncOnOk = jest.fn(
+      () =>
+        new Promise((resolve) => {
+          setTimeout(() => {
+            resolve();
+          }, 1000);
+        })
+    );
+    const promise = prompt('Message', '', {
+      async onOk() {
+        await asyncOnOk();
+      },
+    });
+
+    const okButton = screen.getByRole('button', { name: '确定' });
+    userEvent.click(okButton);
+
+    expect(asyncOnOk).toHaveBeenCalled();
+
+    await act(() => promise);
+  });
+
   describe('waits for async onOk', () => {
     it('shows loading on ok button', async () => {
       const asyncOnOk = jest.fn(
diff --git a/src/utils.js b/src/utils.js
index 48ecfb3..a95f3a5 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -1,8 +1,3 @@
-/**
- * https://stackoverflow.com/a/7356528/8106429
- */
-export function isFunction(functionToCheck) {
-  return (
-    functionToCheck && {}.toString.call(functionToCheck) === '[object Function]'
-  );
+export function isFunction(value) {
+  return typeof value === 'function';
 }