diff --git a/improved_diffusion/dist_util.py b/improved_diffusion/dist_util.py
index f665604d6b..d2c509be64 100644
--- a/improved_diffusion/dist_util.py
+++ b/improved_diffusion/dist_util.py
@@ -69,7 +69,7 @@ def sync_params(params):
     """
     for p in params:
         with th.no_grad():
-            dist.broadcast(p, 0)
+            dist.broadcast(p.detach(), 0)
 
 
 def _find_free_port():