diff --git a/deepspeed/runtime/zero/stage_1_and_2.py b/deepspeed/runtime/zero/stage_1_and_2.py
index 6cfcc418e71a..68385af04ba2 100755
--- a/deepspeed/runtime/zero/stage_1_and_2.py
+++ b/deepspeed/runtime/zero/stage_1_and_2.py
@@ -1308,7 +1308,7 @@ def complete_grad_norm_calculation_for_cpu_offload(self, params):
         total_norm = total_norm_cuda[0].item()**(1. / norm_type)
 
         if total_norm == float('inf') or total_norm == -float('inf') or total_norm != total_norm:
-            total_norm = -1
+            total_norm = -1.
 
         return total_norm