diff --git a/paddle/api/PaddleAPI.h b/paddle/api/PaddleAPI.h
index 10569a71708463a37c77b519f8022b732dcf8ddb..59798796a249c7e18982e2964cd2150dc10d82f9 100644
--- a/paddle/api/PaddleAPI.h
+++ b/paddle/api/PaddleAPI.h
@@ -953,7 +953,7 @@ public:
 
   Arguments* getForwardOutput();
 
-  Arguments* getLayerOutput(const std::string& layerName);
+  Arguments* getLayerOutput(const std::string& layerName) const;
 };
 
 /// the N-Best results generated from one input sequence.
diff --git a/paddle/api/Trainer.cpp b/paddle/api/Trainer.cpp
index c742614aff97f26e1a10be607f30c0fe61530b09..29cf2aa4501de35d970c4d416d62343d39bb234a 100644
--- a/paddle/api/Trainer.cpp
+++ b/paddle/api/Trainer.cpp
@@ -131,7 +131,7 @@ void Trainer::testOneDataBatch(size_t batchSize, const Arguments& args) {
 void TrainerPrivate::finishTestPeriod() { tester_->finishTestPeriod(); }
 void Trainer::finishTestPeriod() { m->finishTestPeriod(); }
 
-Arguments* Trainer::getLayerOutput(const std::string& layerName) {
+Arguments* Trainer::getLayerOutput(const std::string& layerName) const {
   auto nn = this->m->getGradientMachine();
   CHECK(nn) << "trainerInternal_.getGradientMachine() is not NeuralNetwork";
   return Arguments::createByPaddleArgument(&nn->getLayerOutput(layerName));