diff --git a/tutorials/source_en/advanced_use/mixed_precision.md b/tutorials/source_en/advanced_use/mixed_precision.md
index b88cbd8ec2b4dc17f8dd86e58432df7ab1fd96d7..c4b942be8930294a630da7e2a866eefd15c9aa2a 100644
--- a/tutorials/source_en/advanced_use/mixed_precision.md
+++ b/tutorials/source_en/advanced_use/mixed_precision.md
@@ -84,7 +84,7 @@ label = Tensor(np.zeros([64, 128]).astype(np.float32))
 # Define Loss and Optimizer
 loss = nn.SoftmaxCrossEntropyWithLogits()
 optimizer = Momentum(params=net.trainable_params(), learning_rate=0.1, momentum=0.9)
-train_network = amp.build_train_network(net, optimizer, loss, level="O2", loss_scale_manager=None)
+train_network = amp.build_train_network(net, optimizer, loss, level="O3", loss_scale_manager=None)
 
 # Run training
 output = train_network(predict, label)
diff --git a/tutorials/source_zh_cn/advanced_use/mixed_precision.md b/tutorials/source_zh_cn/advanced_use/mixed_precision.md
index 4cacb8c7a40d5cd55ea31bbc7a078f6dab3ab10e..dbea7ee0a2ab74c45aedc66a4d86a564b6d36384 100644
--- a/tutorials/source_zh_cn/advanced_use/mixed_precision.md
+++ b/tutorials/source_zh_cn/advanced_use/mixed_precision.md
@@ -83,7 +83,7 @@ label = Tensor(np.zeros([64, 128]).astype(np.float32))
 # Define Loss and Optimizer
 loss = nn.SoftmaxCrossEntropyWithLogits()
 optimizer = Momentum(params=net.trainable_params(), learning_rate=0.1, momentum=0.9)
-train_network = amp.build_train_network(net, optimizer, loss, level="O2", loss_scale_manager=None)
+train_network = amp.build_train_network(net, optimizer, loss, level="O3", loss_scale_manager=None)
 
 # Run training
 output = train_network(predict, label)