diff --git a/litellm/proxy/guardrails/guardrail_hooks/bedrock_guardrails.py b/litellm/proxy/guardrails/guardrail_hooks/bedrock_guardrails.py
index fb790a44779..2ce63cee89b 100644
--- a/litellm/proxy/guardrails/guardrail_hooks/bedrock_guardrails.py
+++ b/litellm/proxy/guardrails/guardrail_hooks/bedrock_guardrails.py
@@ -265,6 +265,14 @@ class BedrockGuardrail(CustomGuardrail, BaseAWSLLM):
             checks = checks.model_dump(exclude_none=True)
         if not isinstance(checks, dict):
             return None
+        unknown_keys = set(checks.keys()) - _BEDROCK_CHECKS_KNOWN_KEYS
+        if unknown_keys:
+            verbose_proxy_logger.warning(
+                "BedrockGuardrail: unrecognized check key(s) %s will be ignored. "
+                "Known keys: %s. Guardrail will fall back to ApplyGuardrail mode.",
+                sorted(unknown_keys),
+                sorted(_BEDROCK_CHECKS_KNOWN_KEYS),
+            )
         cleaned = {
             key: value
             for key, value in checks.items()
diff --git a/tests/guardrails_tests/test_bedrock_guardrails.py b/tests/guardrails_tests/test_bedrock_guardrails.py
index 9bdb6dd159d..67c27b44b5b 100644
--- a/tests/guardrails_tests/test_bedrock_guardrails.py
+++ b/tests/guardrails_tests/test_bedrock_guardrails.py
@@ -20,6 +20,24 @@ def test_bedrock_normalize_checks_keeps_empty_known_check_config():
     }
 
 
+def test_bedrock_normalize_checks_warns_on_unknown_keys(caplog):
+    import logging
+
+    with caplog.at_level(logging.WARNING, logger="LiteLLM Proxy"):
+        result = BedrockGuardrail._normalize_checks({"contentFilter": {}, "typo_key": True})
+    assert result == {"contentFilter": {}}
+    assert any("typo_key" in m for m in caplog.messages)
+
+
+def test_bedrock_normalize_checks_all_unknown_returns_none_with_warning(caplog):
+    import logging
+
+    with caplog.at_level(logging.WARNING, logger="LiteLLM Proxy"):
+        result = BedrockGuardrail._normalize_checks({"snake_case_typo": True})
+    assert result is None
+    assert any("snake_case_typo" in m for m in caplog.messages)
+
+
 @pytest.mark.asyncio
 async def test_bedrock_guardrails_pii_masking():
     # Create proper mock objects