diff --git a/algo/ppo.py b/algo/ppo.py
index f4873d4a7..a93295e84 100644
--- a/algo/ppo.py
+++ b/algo/ppo.py
@@ -71,7 +71,7 @@ def update(self, rollouts):
                     value_losses_clipped = (value_pred_clipped - return_batch).pow(2)
                     value_loss = .5 * torch.max(value_losses, value_losses_clipped).mean()
                 else:
-                    value_loss = F.mse_loss(return_batch, values)
+                    value_loss = 0.5 * F.mse_loss(return_batch, values)
 
                 self.optimizer.zero_grad()
                 (value_loss * self.value_loss_coef + action_loss -