diff --git a/pytorch_lightning/trainer/distrib_parts.py b/pytorch_lightning/trainer/distrib_parts.py
index 7c476708..29bc8178 100644
--- a/pytorch_lightning/trainer/distrib_parts.py
+++ b/pytorch_lightning/trainer/distrib_parts.py
@@ -449,7 +449,7 @@ class TrainerDPMixin(ABC):
         # when dict
         if isinstance(batch, dict):
             for k, v in batch.items():
-                batch[k] = self.__transfer_data_to_device(x, device, gpu_id)
+                batch[k] = self.__transfer_data_to_device(v, device, gpu_id)
 
             return batch