diff --git a/.changeset/cool-spies-leave.md b/.changeset/cool-spies-leave.md
new file mode 100644
index 00000000..dda4e6cf
--- /dev/null
+++ b/.changeset/cool-spies-leave.md
@@ -0,0 +1,5 @@
+---
+'react-simplikit': patch
+---
+
+fix(core/hooks): call cleanup when unmount occurs before async effect resolves
diff --git a/packages/core/src/hooks/useAsyncEffect/useAsyncEffect.spec.ts b/packages/core/src/hooks/useAsyncEffect/useAsyncEffect.spec.ts
index 9f9cf5b0..4d81d1f0 100644
--- a/packages/core/src/hooks/useAsyncEffect/useAsyncEffect.spec.ts
+++ b/packages/core/src/hooks/useAsyncEffect/useAsyncEffect.spec.ts
@@ -89,6 +89,25 @@ describe('useAsyncEffect', () => {
     expect(cleanup).toHaveBeenCalled();
   });
 
+  it('should call cleanup even when component unmounts before async effect resolves', async () => {
+    const cleanup = vi.fn();
+    const { unmount } = await renderHookSSR(() =>
+      useAsyncEffect(async () => {
+        await new Promise(resolve => setTimeout(resolve, 1000));
+        return cleanup;
+      }, [])
+    );
+
+    await flushPromises();
+    unmount();
+    expect(cleanup).not.toHaveBeenCalled();
+
+    vi.advanceTimersByTime(1000);
+    await flushPromises();
+
+    expect(cleanup).toHaveBeenCalledTimes(1);
+  });
+
   it('should call effect every rerender when deps are undefined', async () => {
     const effect = vi.fn().mockResolvedValue(undefined);
 
diff --git a/packages/core/src/hooks/useAsyncEffect/useAsyncEffect.ts b/packages/core/src/hooks/useAsyncEffect/useAsyncEffect.ts
index 7fade4bc..6394359a 100644
--- a/packages/core/src/hooks/useAsyncEffect/useAsyncEffect.ts
+++ b/packages/core/src/hooks/useAsyncEffect/useAsyncEffect.ts
@@ -24,12 +24,17 @@ import { DependencyList, useEffect } from 'react';
 export function useAsyncEffect(effect: () => Promise<void | (() => void)>, deps?: DependencyList) {
   useEffect(() => {
     let cleanup: (() => void) | void;
+    let isCleaned = false;
 
     effect().then(result => {
       cleanup = result;
+      if (isCleaned) {
+        cleanup?.();
+      }
     });
 
     return () => {
+      isCleaned = true;
       cleanup?.();
     };