diff --git a/.env.example b/.env.example
index e4e5646..f0b307e 100644
--- a/.env.example
+++ b/.env.example
@@ -2,6 +2,7 @@ DISCORD_TOKEN=your_bot_token_here
 MORNING_TIME=07:00
 MORNING_CHANNEL_ID=channel_id
 LOG_LEVEL=INFO
+CAT_API_KEY=your_cat_api_key_here
 CAT_API_RATE=1
 CAT_API_BURST=3
 WEATHER_API_RATE=1
diff --git a/tests/test_fetch_cat.py b/tests/test_fetch_cat.py
index 9f31afe..4a5bb79 100644
--- a/tests/test_fetch_cat.py
+++ b/tests/test_fetch_cat.py
@@ -97,3 +97,28 @@ class TestFetchCat:
         mock_get.return_value = mock_response
         result = await fetch_cat()
         assert result == "https://example.com/cat?w=100&h=200"
+
+    @patch("utils.cat._session.get")
+    @patch("utils.cat._cat_api_key", "test-api-key-123")
+    async def test_fetch_cat_sends_api_key_header(self, mock_get) -> None:
+        """При заданном CAT_API_KEY должен передаваться заголовок x-api-key."""
+        mock_response = MagicMock()
+        mock_response.json.return_value = [{"url": "https://example.com/cat.jpg"}]
+        mock_response.raise_for_status = MagicMock()
+        mock_get.return_value = mock_response
+        await fetch_cat()
+        # Проверяем, что headers переданы с x-api-key
+        call_kwargs = mock_get.call_args
+        assert call_kwargs[1].get("headers") == {"x-api-key": "test-api-key-123"}
+
+    @patch("utils.cat._session.get")
+    @patch("utils.cat._cat_api_key", None)
+    async def test_fetch_cat_no_api_key_header(self, mock_get) -> None:
+        """При отсутствии CAT_API_KEY заголовок x-api-key не передаётся."""
+        mock_response = MagicMock()
+        mock_response.json.return_value = [{"url": "https://example.com/cat.jpg"}]
+        mock_response.raise_for_status = MagicMock()
+        mock_get.return_value = mock_response
+        await fetch_cat()
+        call_kwargs = mock_get.call_args
+        assert call_kwargs[1].get("headers") is None
diff --git a/utils/cat.py b/utils/cat.py
index 8179376..0b4867f 100644
--- a/utils/cat.py
+++ b/utils/cat.py
@@ -1,5 +1,6 @@
 import asyncio
 import logging
+import os
 
 import requests
 
@@ -8,6 +9,7 @@ from utils.rate_limiter import cat_limiter
 logger = logging.getLogger(__name__)
 
 CAT_API_URL = "https://api.thecatapi.com/v1/images/search"
+_cat_api_key: str | None = os.getenv("CAT_API_KEY")
 
 _session = requests.Session()
 
@@ -15,8 +17,13 @@ _session = requests.Session()
 async def fetch_cat() -> str | None:
     """Получить URL случайного котика. Вернуть None при ошибке."""
     await cat_limiter.acquire()
+    headers: dict[str, str] | None = None
+    if _cat_api_key:
+        headers = {"x-api-key": _cat_api_key}
     try:
-        response = await asyncio.to_thread(_session.get, CAT_API_URL, timeout=10)
+        response = await asyncio.to_thread(
+            _session.get, CAT_API_URL, timeout=10, headers=headers
+        )
         response.raise_for_status()
         data = response.json()
         return data[0]["url"]