diff --git a/mmcv/device/mlu/scatter_gather.py b/mmcv/device/mlu/scatter_gather.py
index a3cbbd3a79..0b0c9b96f5 100644
--- a/mmcv/device/mlu/scatter_gather.py
+++ b/mmcv/device/mlu/scatter_gather.py
@@ -16,7 +16,7 @@ def scatter_map(obj):
         if isinstance(obj, torch.Tensor):
             if target_mlus != [-1]:
                 obj = obj.to('mlu')
-                return obj
+                return [obj]
             else:
                 # for CPU inference we use self-implemented scatter
                 return Scatter.forward(target_mlus, obj)