diff --git a/tests/system/vertexai/test_generative_models.py b/tests/system/vertexai/test_generative_models.py
index 2f05d659c8..8cb7d9164f 100644
--- a/tests/system/vertexai/test_generative_models.py
+++ b/tests/system/vertexai/test_generative_models.py
@@ -596,3 +596,16 @@ def test_count_tokens_from_text(self):
             response_with_si_and_tool.total_billable_characters
             > response_with_si.total_billable_characters
         )
+        # content + generation_config
+        response_with_generation_config = model.count_tokens(
+            content,
+            generation_config=generative_models.GenerationConfig(response_schema=_RESPONSE_SCHEMA_STRUCT),
+        )
+        assert (
+            response_with_generation_config.total_tokens
+            > response_with_si_and_tool.total_tokens
+        )
+        assert (
+            response_with_generation_config.total_billable_characters
+            > response_with_si_and_tool.total_billable_characters
+        )
diff --git a/vertexai/generative_models/_generative_models.py b/vertexai/generative_models/_generative_models.py
index 805123bc1d..adf82a0e92 100644
--- a/vertexai/generative_models/_generative_models.py
+++ b/vertexai/generative_models/_generative_models.py
@@ -872,7 +872,7 @@ async def async_generator():
         return async_generator()
 
     def count_tokens(
-        self, contents: ContentsType, *, tools: Optional[List["Tool"]] = None
+        self, contents: ContentsType, *, tools: Optional[List["Tool"]] = None, generation_config: Optional["GenerationConfig"] = None,
     ) -> gapic_prediction_service_types.CountTokensResponse:
         """Counts tokens.
 
@@ -885,6 +885,7 @@ def count_tokens(
                 * List[Union[str, Image, Part]],
                 * List[Content]
             tools: A list of tools (functions) that the model can try calling.
+            generation_config: Parameters for the generate_content method.
 
         Returns:
             A CountTokensResponse object that has the following attributes:
@@ -894,6 +895,7 @@ def count_tokens(
         request = self._prepare_request(
             contents=contents,
             tools=tools,
+            generation_config=generation_config,
         )
         return self._gapic_count_tokens(
             prediction_resource_name=self._prediction_resource_name,
@@ -907,6 +909,7 @@ async def count_tokens_async(
         contents: ContentsType,
         *,
         tools: Optional[List["Tool"]] = None,
+        generation_config: Optional["GenerationConfig"] = None,
     ) -> gapic_prediction_service_types.CountTokensResponse:
         """Counts tokens asynchronously.
 
@@ -919,6 +922,7 @@ async def count_tokens_async(
                 * List[Union[str, Image, Part]],
                 * List[Content]
             tools: A list of tools (functions) that the model can try calling.
+            generation_config: Parameters for the generate_content method.
 
         Returns:
             And awaitable for a CountTokensResponse object that has the following attributes:
@@ -928,6 +932,7 @@ async def count_tokens_async(
         request = self._prepare_request(
             contents=contents,
             tools=tools,
+            generation_config=generation_config,
         )
         return await self._gapic_count_tokens_async(
             prediction_resource_name=self._prediction_resource_name,
@@ -942,6 +947,7 @@ def _gapic_count_tokens(
         contents: List[gapic_content_types.Content],
         system_instruction: Optional[gapic_content_types.Content] = None,
         tools: Optional[List[gapic_tool_types.Tool]] = None,
+        generation_config: Optional[gapic_content_types.GenerationConfig] = None,
     ) -> gapic_prediction_service_types.CountTokensResponse:
         request = gapic_prediction_service_types.CountTokensRequest(
             endpoint=prediction_resource_name,
@@ -949,6 +955,7 @@ def _gapic_count_tokens(
             contents=contents,
             system_instruction=system_instruction,
             tools=tools,
+            generation_config=generation_config,
         )
         return self._prediction_client.count_tokens(request=request)
 
@@ -958,6 +965,7 @@ async def _gapic_count_tokens_async(
         contents: List[gapic_content_types.Content],
         system_instruction: Optional[gapic_content_types.Content] = None,
         tools: Optional[List[gapic_tool_types.Tool]] = None,
+        generation_config: Optional[gapic_content_types.GenerationConfig] = None,
     ) -> gapic_prediction_service_types.CountTokensResponse:
         request = gapic_prediction_service_types.CountTokensRequest(
             endpoint=prediction_resource_name,
@@ -965,6 +973,7 @@ async def _gapic_count_tokens_async(
             contents=contents,
             system_instruction=system_instruction,
             tools=tools,
+            generation_config=generation_config,
         )
         return await self._prediction_async_client.count_tokens(request=request)