diff --git a/homeassistant/components/local_todo/store.py b/homeassistant/components/local_todo/store.py
index 79d5adb217f9..9cf35f03b306 100644
--- a/homeassistant/components/local_todo/store.py
+++ b/homeassistant/components/local_todo/store.py
@@ -24,7 +24,7 @@ class LocalTodoListStore:
         """Load the calendar from disk."""
         if not self._path.exists():
             return ""
-        return self._path.read_text()
+        return self._path.read_text(encoding="utf-8")
 
     async def async_store(self, ics_content: str) -> None:
         """Persist the calendar to storage."""
@@ -33,4 +33,4 @@ class LocalTodoListStore:
 
     def _store(self, ics_content: str) -> None:
         """Persist the calendar to storage."""
-        self._path.write_text(ics_content)
+        self._path.write_text(ics_content, encoding="utf-8")
diff --git a/tests/components/local_todo/conftest.py b/tests/components/local_todo/conftest.py
index ab73dabb4744..2192efe89d83 100644
--- a/tests/components/local_todo/conftest.py
+++ b/tests/components/local_todo/conftest.py
@@ -55,7 +55,9 @@ class FakeStore(LocalTodoListStore):
     def _mock_exists(self) -> bool:
         return self._mock_path.read_text.return_value is not None
 
-    def _mock_write_text(self, content: str) -> None:
+    def _mock_write_text(self, content: str, encoding: str | None = None) -> None:
+        if encoding is None:
+            content.encode("ascii")
         self._mock_path.read_text.return_value = content
 
 
diff --git a/tests/components/local_todo/test_todo.py b/tests/components/local_todo/test_todo.py
index d293fcd36edd..f01597e89e19 100644
--- a/tests/components/local_todo/test_todo.py
+++ b/tests/components/local_todo/test_todo.py
@@ -98,6 +98,10 @@ EXPECTED_ADD_ITEM = {
         ),
         ({ATTR_DESCRIPTION: ""}, {**EXPECTED_ADD_ITEM, "description": ""}),
         ({ATTR_DESCRIPTION: None}, EXPECTED_ADD_ITEM),
+        (
+            {ATTR_ITEM: "测试主卧清扫"},
+            {**EXPECTED_ADD_ITEM, "summary": "测试主卧清扫"},
+        ),
     ],
 )
 async def test_add_item(