diff --git a/packages/location-state-core/src/stores/storage-store.test.ts b/packages/location-state-core/src/stores/storage-store.test.ts
index 83c772b1..35278693 100644
--- a/packages/location-state-core/src/stores/storage-store.test.ts
+++ b/packages/location-state-core/src/stores/storage-store.test.ts
@@ -127,6 +127,24 @@ test("On `load` called with serializer, if the value of the corresponding key is
   expect(store.get("foo")).toBe("dummy-result");
 });
 
+test("On `load` called with invalid serializer, the value of slice remains at its initial value.", () => {
+  // Arrange
+  const navigationKey = "current_location";
+  storageMock.getItem.mockReturnValueOnce(
+    JSON.stringify({ foo: "storage value" }),
+  );
+  const store = new StorageStore(storage, {
+    serialize: JSON.stringify,
+    deserialize: () => {
+      throw new Error("deserialize error");
+    },
+  });
+  // Act
+  store.load(navigationKey);
+  // Assert
+  expect(store.get("foo")).toBeUndefined();
+});
+
 test("On `load` called, all listener notified.", async () => {
   // Arrange
   const navigationKey = "current_location";
@@ -181,6 +199,24 @@ test("On `save` called with serializer, the state is saved in Storage with the p
   );
 });
 
+test("On `save` called with invalid serializer, the state is not saved in Storage.", () => {
+  // Arrange
+  const currentLocationKey = "current_location";
+  const store = new StorageStore(storage, {
+    serialize: () => {
+      throw new Error("serialize error");
+    },
+    deserialize: JSON.parse,
+  });
+  store.load(currentLocationKey);
+  store.set("foo", "updated");
+  // Act
+  store.save();
+  // Assert
+  expect(store.get("foo")).toBe("updated");
+  expect(storageMock.setItem).not.toBeCalled();
+});
+
 test("Calling `save` with empty will remove the Storage with Location key.", () => {
   // Arrange
   const currentLocationKey = "current_location";
diff --git a/packages/location-state-core/src/stores/storage-store.ts b/packages/location-state-core/src/stores/storage-store.ts
index 5cd8d069..e5994c23 100644
--- a/packages/location-state-core/src/stores/storage-store.ts
+++ b/packages/location-state-core/src/stores/storage-store.ts
@@ -59,7 +59,11 @@ export class StorageStore implements Store {
     this.currentKey = locationKey;
     const value = this.storage?.getItem(this.createStorageKey()) ?? null;
     if (value !== null) {
-      this.state = this.serializer.deserialize(value);
+      try {
+        this.state = this.serializer.deserialize(value);
+      } catch (e) {
+        this.state = {};
+      }
     } else {
       this.state = {};
     }
@@ -74,10 +78,13 @@ export class StorageStore implements Store {
       this.storage?.removeItem(this.createStorageKey());
       return;
     }
-    this.storage?.setItem(
-      this.createStorageKey(),
-      this.serializer.serialize(this.state),
-    );
+    let value: string;
+    try {
+      value = this.serializer.serialize(this.state);
+    } catch (e) {
+      return;
+    }
+    this.storage?.setItem(this.createStorageKey(), value);
   }
 
   private createStorageKey() {
diff --git a/packages/location-state-core/src/stores/url-store.test.ts b/packages/location-state-core/src/stores/url-store.test.ts
index 52b1565e..a9e5de24 100644
--- a/packages/location-state-core/src/stores/url-store.test.ts
+++ b/packages/location-state-core/src/stores/url-store.test.ts
@@ -39,7 +39,7 @@ test("If params is empty, the initial value is undefined.", () => {
   expect(slice).toBeUndefined();
 });
 
-test("On `set` called, store's values are updated and reflected in the URL", () => {
+test("On `set` called, store's values are updated and reflected in the URL.", () => {
   // Arrange
   prepareLocation({
     pathname: "/",
@@ -56,7 +56,7 @@ test("On `set` called, store's values are updated and reflected in the URL", ()
   );
 });
 
-test("On `set` called with serializer, store's values are updated and reflected in the URL", () => {
+test("On `set` called with serializer, store's values are updated and reflected in the URL.", () => {
   // Arrange
   prepareLocation({
     pathname: "/",
@@ -78,6 +78,30 @@ test("On `set` called with serializer, store's values are updated and reflected
   );
 });
 
+test("On `set` called with invalid serializer, store's values are initial value and not reflected in the URL.", () => {
+  // Arrange
+  const consoleSpy = jest.spyOn(console, "error").mockImplementation();
+  prepareLocation({
+    pathname: "/",
+    search: "?hoge=fuga",
+  });
+  const store = new URLStore("store-key", syncerMock, {
+    serialize: () => {
+      throw new Error("serialize error");
+    },
+    deserialize: () => ({
+      foo: "not-used-value",
+    }),
+  });
+  // Act
+  store.set("foo", "updated");
+  // Assert
+  expect(store.get("foo")).toBe("updated");
+  expect(syncerMock.updateURL).not.toHaveBeenCalled();
+  // post processing
+  consoleSpy.mockRestore();
+});
+
 test("listener is called when updating slice.", () => {
   // Arrange
   const store = new URLStore("store-key", syncerMock);
@@ -168,6 +192,29 @@ test("On `load` called with serializer, the value is obtained through serialize.
   expect(store.get("foo")).toBe("dummy-result");
 });
 
+test("On `load` called with invalid serializer, the value is initial value.", () => {
+  // Arrange
+  const consoleSpy = jest.spyOn(console, "error").mockImplementation();
+  prepareLocation({
+    pathname: "/",
+    search: "?store-key=%7B%22foo%22%3A%22updated%22%7D",
+  });
+  const store = new URLStore("store-key", syncerMock, {
+    serialize: JSON.stringify,
+    deserialize: () => {
+      throw new Error("deserialize error");
+    },
+  });
+  // Act
+  store.load();
+  // Assert
+  expect(store.get("foo")).toBeUndefined();
+  expect(syncerMock.updateURL).toHaveBeenCalledTimes(1);
+  expect(syncerMock.updateURL).toHaveBeenCalledWith("http://localhost/");
+  // post processing
+  consoleSpy.mockRestore();
+});
+
 test("On `load` called, all listener notified.", async () => {
   // Arrange
   const store = new URLStore("store-key", syncerMock);
diff --git a/packages/location-state-core/src/stores/url-store.ts b/packages/location-state-core/src/stores/url-store.ts
index d3710054..7499a5f0 100644
--- a/packages/location-state-core/src/stores/url-store.ts
+++ b/packages/location-state-core/src/stores/url-store.ts
@@ -55,7 +55,14 @@ export class URLStore implements Store {
     } else {
       this.state[name] = value;
     }
-    this.stateJSON = this.serializer.serialize(this.state);
+    try {
+      this.stateJSON = this.serializer.serialize(this.state);
+    } catch (e) {
+      console.error(e);
+      this.notify(name);
+      // Not reflected in URL.
+      return;
+    }
     // save to url
     const url = new URL(location.href);
     url.searchParams.set(this.key, this.stateJSON);