diff --git a/src/mlpack/methods/ann/layer/adaptive_mean_pooling_impl.hpp b/src/mlpack/methods/ann/layer/adaptive_mean_pooling_impl.hpp
index f397826bb4..8ad2aad0b8 100644
--- a/src/mlpack/methods/ann/layer/adaptive_mean_pooling_impl.hpp
+++ b/src/mlpack/methods/ann/layer/adaptive_mean_pooling_impl.hpp
@@ -146,6 +146,8 @@ void AdaptiveMeanPoolingType<MatType>::serialize(
   ar(cereal::base_class<Layer<MatType>>(this));
 
   ar(CEREAL_NVP(poolingLayer));
+  ar(CEREAL_NVP(outputWidth));
+  ar(CEREAL_NVP(outputHeight));
 }
 
 } // namespace ann