diff --git a/returnn/torch/engine.py b/returnn/torch/engine.py
index b07be4052..445dfab05 100644
--- a/returnn/torch/engine.py
+++ b/returnn/torch/engine.py
@@ -134,6 +134,13 @@ def __init__(self, config: Config):
         self._forward_auto_split_batch_on_oom = config.bool("forward_auto_split_batch_on_oom", False)
         self._stop_on_nonfinite_train_score = config.bool("stop_on_nonfinite_train_score", True)
 
+        if config.bool("use_tensorboard", False):
+            from torch.utils.tensorboard import SummaryWriter
+
+            self._tensorboard_writer = SummaryWriter()
+        else:
+            self._tensorboard_writer = None
+
         default_float_dtype = config.value("default_float_dtype", None)
         if default_float_dtype is not None:
             assert isinstance(default_float_dtype, str)
@@ -257,6 +264,9 @@ def train(self):
             self.init_train_epoch()
             self.train_epoch()
 
+        if self._tensorboard_writer:
+            self._tensorboard_writer.close()
+
         print(f"Finished training at epoch {self.epoch}, global train step {self.global_train_step}", file=log.v3)
 
     def init_train_epoch(self):
@@ -506,6 +516,10 @@ def train_epoch(self):
                     batch_size_info=_get_batch_size_info(extern_data) if self._log_batch_size else None,
                     log_memory_usage_device=self._device if self._log_memory_usage else None,
                 )
+                if self._tensorboard_writer:
+                    # write losses/errors to tensorboard
+                    for key, val in eval_info.items():
+                        self._tensorboard_writer.add_scalar(f"train/{key}", val, global_step=self.global_train_step)
 
                 if self._stop_on_nonfinite_train_score:
                     if any(np.isinf(v) or np.isnan(v) for v in accumulated_losses_dict.values()):
@@ -695,12 +709,18 @@ def eval_model(self, *, skip_already_evaluated: bool = False):
                         start_elapsed=step_end_time - eval_start_time,
                         log_memory_usage_device=self._device if self._log_memory_usage else None,
                     )
+
                     step_idx += 1
 
             assert step_idx > 0, f"No data in dataset {dataset_name!r}."
             accumulated_losses_dict = accumulated_losses_dict / accumulated_inv_norm_factors_dict
             accumulated_losses_dict = self._maybe_extend_losses_info(accumulated_losses_dict)
 
+            if self._tensorboard_writer:
+                # write losses/errors to tensorboard
+                for key, val in accumulated_losses_dict.items():
+                    self._tensorboard_writer.add_scalar(f"{dataset_name}/{key}", val, global_step=self.epoch)
+
             self.learning_rate_control.set_epoch_error(
                 self.epoch, {f"{dataset_name}_loss_{k}": v for k, v in accumulated_losses_dict.items()}
             )