diff --git a/cpp/tensorrt_llm/batch_manager/trtGptModelInflightBatching.cpp b/cpp/tensorrt_llm/batch_manager/trtGptModelInflightBatching.cpp
index b8855af568d..be7397182ec 100644
--- a/cpp/tensorrt_llm/batch_manager/trtGptModelInflightBatching.cpp
+++ b/cpp/tensorrt_llm/batch_manager/trtGptModelInflightBatching.cpp
@@ -559,7 +559,7 @@ TrtGptModelInflightBatching::clampWindowSizesToFitAtLeastOneSequence(BlocksPerWi
     TLLM_LOG_WARNING("maxAttentionWindowVec too large to fit at least one sequence in kvCache. Old: %s, New: %s",
         common::vec2str(getMaxAttentionWindowVec()).c_str(), common::vec2str(newMaxAttentionWindowVec).c_str());
     setMaxAttentionWindowVec(newMaxAttentionWindowVec);
-    if (getMaxSequenceLen() < getMaxAttentionWindow())
+    if (getMaxSequenceLen() > getMaxAttentionWindow())
     {
         TLLM_LOG_WARNING("maxSequenceLen is reduced to maxAttentionWindow: %d", getMaxAttentionWindow());
         setMaxSequenceLen(getMaxAttentionWindow());
diff --git a/cpp/tests/batch_manager/trtGptModelTest.cpp b/cpp/tests/batch_manager/trtGptModelTest.cpp
index d45aedcabb1..1f1f5743725 100644
--- a/cpp/tests/batch_manager/trtGptModelTest.cpp
+++ b/cpp/tests/batch_manager/trtGptModelTest.cpp
@@ -870,6 +870,11 @@ class TrtGptModelIfbHelper : public TrtGptModelInflightBatching
     {
         return TrtGptModelInflightBatching::getKVCacheManager();
     }
+
+    [[nodiscard]] SizeType32 getMaxAttentionWindow() const
+    {
+        return TrtGptModelInflightBatching::getMaxAttentionWindow();
+    }
 };
 
 TEST_F(TrtGptModelTest, KVCacheReuseChunked)
@@ -1201,4 +1206,23 @@ TEST_F(LlamaModelLADTest, SeamlessLookaheadDecoding)
     }
 }
 
+TEST_F(TrtGptModelTest, ClampSeqLenToAttentionWindow)
+{
+    auto constexpr maxAttentionWindow = 65536;
+    auto constexpr maxSequenceLen = maxAttentionWindow + 1;
+
+    TrtGptModelOptionalParams optionalParams;
+    optionalParams.kvCacheConfig.maxAttentionWindowVec = std::vector<SizeType32>{maxAttentionWindow};
+    optionalParams.kvCacheConfig.freeGpuMemoryFraction = 0.0001; // minuscule amount of memory to force a clamp
+    optionalParams.maxBeamWidth = mBeamWidth;
+
+    auto modelConfig = mModelConfig;
+    modelConfig.setMaxSequenceLen(maxSequenceLen);
+
+    auto trtGptModel
+        = std::make_shared<TrtGptModelIfbHelper>(mLogger, modelConfig, mWorldConfig, *mRawEngine, true, optionalParams);
+    EXPECT_LT(trtGptModel->getMaxAttentionWindow(), maxAttentionWindow);
+    EXPECT_EQ(trtGptModel->getMaxSequenceLen(), trtGptModel->getMaxAttentionWindow());
+}
+
 } // namespace tensorrt_llm::batch_manager