diff --git a/python/paddle/fluid/tests/book_memory_optimization/test_memopt_fit_a_line.py b/python/paddle/fluid/tests/book_memory_optimization/test_memopt_fit_a_line.py
index 7648bb9fe1c8d2dae3590fa67f781743ba297c32..a99d13330b84e07a04a4499d749df24ec99e7ec0 100644
--- a/python/paddle/fluid/tests/book_memory_optimization/test_memopt_fit_a_line.py
+++ b/python/paddle/fluid/tests/book_memory_optimization/test_memopt_fit_a_line.py
@@ -31,7 +31,7 @@ use_nccl = False
 place = fluid.CPUPlace()
 if fluid.core.is_compiled_with_cuda():
     device_type = 'CUDA'
-    use_nccl = False
+    use_nccl = True
     place = fluid.CUDAPlace(0)
 
 places = fluid.layers.get_places(device_count=0, device_type=device_type)