diff --git a/src/diffusers/schedulers/scheduling_unipc_multistep.py b/src/diffusers/schedulers/scheduling_unipc_multistep.py
index 5c2cbcc13ff1..3a703d655a7f 100644
--- a/src/diffusers/schedulers/scheduling_unipc_multistep.py
+++ b/src/diffusers/schedulers/scheduling_unipc_multistep.py
@@ -356,7 +356,7 @@ def set_timesteps(
                 .astype(np.int64)
             )
         elif self.config.timestep_spacing == "leading":
-            step_ratio = self.config.num_train_timesteps // (num_inference_steps + 1)
+            step_ratio = self.config.num_train_timesteps // (num_inference_steps)
             # creates integer timesteps by multiplying by ratio
             # casting to int to avoid issues when num_inference_step is power of 3
             timesteps = (np.arange(0, num_inference_steps + 1) * step_ratio).round()[::-1][:-1].copy().astype(np.int64)