diff --git a/mmdet/models/losses/balanced_l1_loss.py b/mmdet/models/losses/balanced_l1_loss.py
index dccb9e5b89ff86711729890cd6c58d31f0836d9b..2dee6742b7431b5443da5505de345acee45ada70 100644
--- a/mmdet/models/losses/balanced_l1_loss.py
+++ b/mmdet/models/losses/balanced_l1_loss.py
@@ -2,7 +2,7 @@ import numpy as np
 import torch
 import torch.nn as nn
 
-from .utils import reduce_loss, weighted_loss
+from .utils import weighted_loss
 from ..registry import LOSSES
 
 
@@ -23,8 +23,6 @@ def balanced_l1_loss(pred,
         (b * diff + 1) * torch.log(b * diff / beta + 1) - alpha * diff,
         gamma * diff + gamma / b - alpha * beta)
 
-    loss = reduce_loss(loss, reduction)
-
     return loss