diff --git a/homeassistant/components/google_generative_ai_conversation/__init__.py b/homeassistant/components/google_generative_ai_conversation/__init__.py
index 89fba79fced4b..d1b8467955a88 100644
--- a/homeassistant/components/google_generative_ai_conversation/__init__.py
+++ b/homeassistant/components/google_generative_ai_conversation/__init__.py
@@ -73,6 +73,9 @@ async def generate_content(call: ServiceCall) -> ServiceResponse:
         ) as err:
             raise HomeAssistantError(f"Error generating content: {err}") from err
 
+        if not response.parts:
+            raise HomeAssistantError("Error generating content")
+
         return {"text": response.text}
 
     hass.services.async_register(
diff --git a/tests/components/google_generative_ai_conversation/test_init.py b/tests/components/google_generative_ai_conversation/test_init.py
index daae858259446..7dfa8bebfa5ef 100644
--- a/tests/components/google_generative_ai_conversation/test_init.py
+++ b/tests/components/google_generative_ai_conversation/test_init.py
@@ -110,6 +110,30 @@ async def test_generate_content_service_error(
         )
 
 
+@pytest.mark.usefixtures("mock_init_component")
+async def test_generate_content_response_has_empty_parts(
+    hass: HomeAssistant,
+    mock_config_entry: MockConfigEntry,
+) -> None:
+    """Test generate content service handles response with empty parts."""
+    with (
+        patch("google.generativeai.GenerativeModel") as mock_model,
+        pytest.raises(HomeAssistantError, match="Error generating content"),
+    ):
+        mock_response = MagicMock()
+        mock_response.parts = []
+        mock_model.return_value.generate_content_async = AsyncMock(
+            return_value=mock_response
+        )
+        await hass.services.async_call(
+            "google_generative_ai_conversation",
+            "generate_content",
+            {"prompt": "write a story about an epic fail"},
+            blocking=True,
+            return_response=True,
+        )
+
+
 async def test_generate_content_service_with_image_not_allowed_path(
     hass: HomeAssistant,
     mock_config_entry: MockConfigEntry,