diff --git a/litellm/llms/bedrock/chat/invoke_handler.py b/litellm/llms/bedrock/chat/invoke_handler.py
index fc34e403beb..adddfa55f72 100644
--- a/litellm/llms/bedrock/chat/invoke_handler.py
+++ b/litellm/llms/bedrock/chat/invoke_handler.py
@@ -829,6 +829,16 @@ class MockResponseIterator:  # for returning ai21 streaming responses
                     prompt_tokens=chunk_usage.prompt_tokens,
                     completion_tokens=chunk_usage.completion_tokens,
                     total_tokens=chunk_usage.total_tokens,
+                    prompt_tokens_details=(
+                        chunk_usage.prompt_tokens_details.model_dump(exclude_none=True)
+                        if chunk_usage.prompt_tokens_details is not None
+                        else None
+                    ),
+                    completion_tokens_details=(
+                        chunk_usage.completion_tokens_details.model_dump(exclude_none=True)
+                        if chunk_usage.completion_tokens_details is not None
+                        else None
+                    ),
                 ),
                 index=0,
             )
diff --git a/tests/test_litellm/llms/bedrock/chat/test_invoke_handler.py b/tests/test_litellm/llms/bedrock/chat/test_invoke_handler.py
index 4bef59842f1..d877b70f71d 100644
--- a/tests/test_litellm/llms/bedrock/chat/test_invoke_handler.py
+++ b/tests/test_litellm/llms/bedrock/chat/test_invoke_handler.py
@@ -9,10 +9,57 @@ from litellm.litellm_core_utils.litellm_logging import Logging as LiteLLMLogging
 from litellm.litellm_core_utils.streaming_handler import CustomStreamWrapper
 from litellm.llms.bedrock.chat.invoke_handler import (
     AWSEventStreamDecoder,
+    MockResponseIterator,
     make_call,
     make_sync_call,
 )
 from litellm.llms.custom_httpx.http_handler import AsyncHTTPHandler, HTTPHandler
+from litellm.types.utils import (
+    Choices,
+    CompletionTokensDetailsWrapper,
+    Message,
+    ModelResponse,
+    PromptTokensDetailsWrapper,
+    Usage,
+)
+
+
+def test_mock_response_iterator_preserves_usage_details():
+    response = ModelResponse(
+        choices=[
+            Choices(
+                finish_reason="stop",
+                index=0,
+                message=Message(content="done", role="assistant"),
+            )
+        ],
+        usage=Usage(
+            prompt_tokens=500,
+            completion_tokens=25,
+            total_tokens=525,
+            prompt_tokens_details=PromptTokensDetailsWrapper(
+                cached_tokens=321,
+                cache_write_tokens=123,
+            ),
+            completion_tokens_details=CompletionTokensDetailsWrapper(
+                reasoning_tokens=11,
+            ),
+        ),
+    )
+
+    chunk = MockResponseIterator(model_response=response)._chunk_parser(response)
+
+    assert chunk["usage"] == {
+        "prompt_tokens": 500,
+        "completion_tokens": 25,
+        "total_tokens": 525,
+        "prompt_tokens_details": {
+            "cached_tokens": 321,
+            "cache_write_tokens": 123,
+            "cache_creation_tokens": 123,
+        },
+        "completion_tokens_details": {"reasoning_tokens": 11},
+    }
 
 
 def test_transform_thinking_blocks_with_redacted_content():
@@ -495,4 +542,3 @@ async def test_async_invoke_streaming_forwards_bedrock_response_headers():
     )
 
     assert stream._hidden_params["additional_headers"]["llm_provider-x-amzn-requestid"] == "req-987"
-