diff --git a/haystack/components/generators/chat/azure.py b/haystack/components/generators/chat/azure.py
index 5b78d03c35..f5907fcdbe 100644
--- a/haystack/components/generators/chat/azure.py
+++ b/haystack/components/generators/chat/azure.py
@@ -324,7 +324,7 @@ def to_dict(self) -> dict[str, Any]:
         # If it's already a json schema, it's left as is
         generation_kwargs = self.generation_kwargs.copy()
         response_format = generation_kwargs.get("response_format")
-        if response_format and issubclass(response_format, BaseModel):
+        if response_format and isinstance(response_format, type) and issubclass(response_format, BaseModel):
             json_schema = {
                 "type": "json_schema",
                 "json_schema": {
diff --git a/releasenotes/notes/fix-azure-chat-generator-to-dict-response-format-1b844d5eaadcbd81.yaml b/releasenotes/notes/fix-azure-chat-generator-to-dict-response-format-1b844d5eaadcbd81.yaml
new file mode 100644
index 0000000000..d6772df2f4
--- /dev/null
+++ b/releasenotes/notes/fix-azure-chat-generator-to-dict-response-format-1b844d5eaadcbd81.yaml
@@ -0,0 +1,4 @@
+---
+fixes:
+  - |
+    Fix crash in ``AzureOpenAIChatGenerator.to_dict()`` when ``response_format`` is passed as a dictionary.
diff --git a/test/components/generators/chat/test_azure.py b/test/components/generators/chat/test_azure.py
index 7b0c1ad019..42c4908834 100644
--- a/test/components/generators/chat/test_azure.py
+++ b/test/components/generators/chat/test_azure.py
@@ -335,8 +335,22 @@ def test_to_dict_with_parameters(self, monkeypatch: pytest.MonkeyPatch, calendar
             },
         }
 
-    def test_from_dict(self, monkeypatch: pytest.MonkeyPatch) -> None:
+    @pytest.mark.parametrize(
+        "rf",
+        [
+            {"type": "json_object"},
+            {"type": "json_schema", "json_schema": {"name": "MySchema", "strict": True, "schema": {}}},
+        ],
+    )
+    def test_to_dict_with_dict_response_format(self, monkeypatch: pytest.MonkeyPatch, rf: dict[str, Any]) -> None:
+        monkeypatch.setenv("AZURE_OPENAI_API_KEY", "test-api-key")
+        component = AzureOpenAIChatGenerator(
+            azure_endpoint="some-non-existing-endpoint", generation_kwargs={"response_format": rf}
+        )
+        data = component.to_dict()
+        assert data["init_parameters"]["generation_kwargs"]["response_format"] == rf
 
+    def test_from_dict(self, monkeypatch: pytest.MonkeyPatch) -> None:
         monkeypatch.setenv("AZURE_OPENAI_API_KEY", "test-api-key")
         monkeypatch.setenv("AZURE_OPENAI_AD_TOKEN", "test-ad-token")
         data = {