diff --git a/torch2trt/torch2trt.py b/torch2trt/torch2trt.py
index 6a33a9ee..1ee0e93f 100644
--- a/torch2trt/torch2trt.py
+++ b/torch2trt/torch2trt.py
@@ -465,7 +465,11 @@ def forward(self, *inputs):
         for i, output_name in enumerate(self.output_names):
             idx = self.engine.get_binding_index(output_name)
             dtype = torch_dtype_from_trt(self.engine.get_binding_dtype(idx))
-            shape = (batch_size,) + tuple(self.engine.get_binding_shape(idx))
+            oshape = tuple(self.engine.get_binding_shape(idx))
+            if oshape[0] == -1:
+                shape = (batch_size, ) + oshape[1:]
+            else:
+                shape = (batch_size,) + oshape
             device = torch_device_from_trt(self.engine.get_location(idx))
             output = torch.empty(size=shape, dtype=dtype, device=device)
             outputs[i] = output
@@ -474,6 +478,12 @@ def forward(self, *inputs):
         for i, input_name in enumerate(self.input_names):
             idx = self.engine.get_binding_index(input_name)
             bindings[idx] = inputs[i].contiguous().data_ptr()
+            ishape = tuple(self.engine.get_binding_shape(idx))
+            if ishape[0] == -1:
+                tmp_ishape = (batch_size,) + ishape[1:]
+                batch_size = 1
+                self.context.set_binding_shape(idx, tmp_ishape)
+
 
         self.context.execute_async(
             batch_size, bindings, torch.cuda.current_stream().cuda_stream