diff --git a/deepspeed/runtime/pipe/engine.py b/deepspeed/runtime/pipe/engine.py
index 367932a95d28d5e89d624661eeeb3b55ac5a14d0..6286aa6cf0c4f9d1d30259a695e87949ec3f6072 100644
--- a/deepspeed/runtime/pipe/engine.py
+++ b/deepspeed/runtime/pipe/engine.py
@@ -243,7 +243,7 @@ class PipelineEngine(DeepSpeedEngine):
         self._force_grad_boundary = True
         if self.pipeline_enable_backward_allreduce:
             if self.bfloat16_enabled():
-                if self.zero_optimization_stage() < ZeroStageEnum().gradients:
+                if self.zero_optimization_stage() < ZeroStageEnum.gradients:
                     self._bf16_reduce_grads()
                 else:
                     raise NotImplementedError("PP+BF16 only work for ZeRO Stage 1")