diff --git a/examples/model_compress/main_torch_pruner.py b/examples/model_compress/main_torch_pruner.py
index 10f7355cd1..17a6b131fe 100644
--- a/examples/model_compress/main_torch_pruner.py
+++ b/examples/model_compress/main_torch_pruner.py
@@ -55,7 +55,7 @@ def test(model, device, test_loader):
 
 def main():
     torch.manual_seed(0)
-    device = torch.device('cpu')
+    device = torch.device('cuda')
 
     trans = transforms.Compose([transforms.ToTensor(), transforms.Normalize((0.1307,), (0.3081,))])
     train_loader = torch.utils.data.DataLoader(
@@ -66,7 +66,7 @@ def main():
         batch_size=1000, shuffle=True)
 
     model = Mnist()
-    model.to(device)
+    model = model.to(device)
 
     '''you can change this to LevelPruner to implement it
     pruner = LevelPruner(configure_list)
@@ -82,14 +82,14 @@ def main():
 
     pruner = AGP_Pruner(model, configure_list)
     model = pruner.compress()
-
+    model = model.to(device)
     optimizer = torch.optim.SGD(model.parameters(), lr=0.01, momentum=0.5)
     for epoch in range(10):
         pruner.update_epoch(epoch)
         print('# Epoch {} #'.format(epoch))
         train(model, device, train_loader, optimizer)
         test(model, device, test_loader)
-    pruner.export_model('model.pth', 'mask.pth', 'model.onnx', [1, 1, 28, 28])
+    pruner.export_model('model.pth', 'mask.pth', 'model.onnx', [1, 1, 28, 28], device)
 
 
 if __name__ == '__main__':
diff --git a/src/sdk/pynni/nni/compression/torch/compressor.py b/src/sdk/pynni/nni/compression/torch/compressor.py
index 14cbc194f7..107db55a0b 100644
--- a/src/sdk/pynni/nni/compression/torch/compressor.py
+++ b/src/sdk/pynni/nni/compression/torch/compressor.py
@@ -226,7 +226,7 @@ def __init__(self, module, module_name, module_type, config, pruner):
         # config and pruner
         self.config = config
         self.pruner = pruner
-        self.registered_buffers = {}
+        self.registered_buffers = []
 
         # register buffer for mask
         self.register_buffer("weight_mask", torch.ones(self.module.weight.shape))
@@ -234,16 +234,21 @@ def __init__(self, module, module_name, module_type, config, pruner):
             self.register_buffer("bias_mask", torch.ones(self.module.bias.shape))
         else:
             self.register_buffer("bias_mask", None)
-
-        self.registered_buffers['weight_mask'] = self.weight_mask
-        self.registered_buffers['bias_mask'] = self.bias_mask
+        self.registered_buffers.append('weight_mask')
+        self.registered_buffers.append('bias_mask')
         # register user specified buffer
         for name in self.pruner.buffers:
             self.register_buffer(name, self.pruner.buffers[name].clone())
-            self.registered_buffers[name] = getattr(self, name)
+            self.registered_buffers.append(name)
+
+    def get_registered_buffers(self):
+        buffers = {}
+        for name in self.registered_buffers:
+            buffers[name] = getattr(self, name)
+        return buffers
 
     def forward(self, *inputs):
-        mask = self.pruner.calc_mask(LayerInfo(self.name, self.module), self.config, **self.registered_buffers)
+        mask = self.pruner.calc_mask(LayerInfo(self.name, self.module), self.config, **self.get_registered_buffers())
         if mask is not None:
             self.weight_mask.copy_(mask['weight'])
         # apply mask to weight
@@ -399,6 +404,7 @@ def __init__(self, module, module_name, module_type, config, quantizer):
         # config and pruner
         self.config = config
         self.quantizer = quantizer
+        self.registered_buffers = []
 
         # register buffer and parameter
         # old_weight is used to store origin weight and weight is used to store quantized weight
@@ -413,10 +419,15 @@ def __init__(self, module, module_name, module_type, config, quantizer):
                 self.module.register_buffer('weight', self.module.old_weight)
 
         # register user specified buffer
-        self.registered_buffers = {}
         for name in self.quantizer.buffers:
             self.register_buffer(name, self.quantizer.buffers[name].clone())
-            self.registered_buffers[name] = getattr(self, name)
+            self.registered_buffers.append(name)
+
+    def get_registered_buffers(self):
+        buffers = {}
+        for name in self.registered_buffers:
+            buffers[name] = getattr(self, name)
+        return buffers
 
     def forward(self, *inputs):
         if 'input' in self.config['quant_types']:
@@ -426,7 +437,7 @@ def forward(self, *inputs):
                 self.quantizer.quantize_input,
                 self.config,
                 LayerInfo(self.name, self.module),
-                **self.registered_buffers)
+                **self.get_registered_buffers())
 
         if 'weight' in self.config['quant_types'] and _check_weight(self.module):
             new_weight = self.quantizer.quant_grad.apply(
@@ -435,7 +446,7 @@ def forward(self, *inputs):
                 self.quantizer.quantize_weight,
                 self.config,
                 LayerInfo(self.name, self.module),
-                **self.registered_buffers)
+                **self.get_registered_buffers())
             self.module.weight = new_weight
             result = self.module(*inputs)
         else:
@@ -448,7 +459,7 @@ def forward(self, *inputs):
                 self.quantizer.quantize_output,
                 self.config,
                 LayerInfo(self.name, self.module),
-                **self.registered_buffers)
+                **self.get_registered_buffers())
         return result
 
 class Quantizer(Compressor):
diff --git a/src/sdk/pynni/nni/compression/torch/pruners.py b/src/sdk/pynni/nni/compression/torch/pruners.py
index b49ed77f2f..f186fb6917 100644
--- a/src/sdk/pynni/nni/compression/torch/pruners.py
+++ b/src/sdk/pynni/nni/compression/torch/pruners.py
@@ -170,7 +170,7 @@ def update_epoch(self, epoch):
         if epoch > 0:
             self.now_epoch = epoch
             for wrapper in self.get_modules_wrapper():
-                wrapper.registered_buffers['if_calculated'].copy_(torch.tensor(0)) # pylint: disable=not-callable
+                wrapper.if_calculated.copy_(torch.tensor(0)) # pylint: disable=not-callable
 
 class SlimPruner(Pruner):
     """