diff --git a/python/paddle/fluid/tests/unittests/CMakeLists.txt b/python/paddle/fluid/tests/unittests/CMakeLists.txt
index 699181d01da862dca72113e6c11630ae5693e41c..4b26bacce968a6da72e9aa043adb38918b293a35 100644
--- a/python/paddle/fluid/tests/unittests/CMakeLists.txt
+++ b/python/paddle/fluid/tests/unittests/CMakeLists.txt
@@ -110,6 +110,10 @@ py_test_modules(test_parallel_executor_transformer MODULES test_parallel_executo
 if(NOT APPLE)
     py_test_modules(test_image_classification_resnet MODULES test_image_classification_resnet SERIAL)
 endif()
+if(CMAKE_BUILD_TYPE STREQUAL "Debug")
+    # change the timeout from 600 to 900, because in debug mode, this test need more time.
+    set_tests_properties(test_image_classification_resnet PROPERTIES TIMEOUT 900)
+endif()
 
 if (WITH_NGRAPH)
     add_subdirectory(ngraph)