diff --git a/paddle/gserver/tests/test_DetectionOutput.cpp b/paddle/gserver/tests/test_DetectionOutput.cpp
index 8ec7a2845028a62c7656e21e2109000ee0af8c6a..af43dc51fad35c834635b543b1a016f6d717de1e 100644
--- a/paddle/gserver/tests/test_DetectionOutput.cpp
+++ b/paddle/gserver/tests/test_DetectionOutput.cpp
@@ -65,9 +65,12 @@ void doOneDetectionOutputTest(MatrixPtr& inputLoc,
   dataLayers[2]->getOutputValue()->copyFrom(*inputConf);
 
   // test layer initialize
+  bool store_FLAGS_use_gpu = FLAGS_use_gpu;
+  FLAGS_use_gpu = use_gpu;
   std::vector<ParameterPtr> parameters;
   LayerPtr detectionOutputLayer;
   initTestLayer(configt, &layerMap, &parameters, &detectionOutputLayer);
+  FLAGS_use_gpu = store_FLAGS_use_gpu;
   detectionOutputLayer->forward(PASS_GC);
   checkMatrixEqual(detectionOutputLayer->getOutputValue(), result);
 }