diff --git a/diffsynth/diffusion/loss.py b/diffsynth/diffusion/loss.py
index ae44bb683..14fdfd3be 100644
--- a/diffsynth/diffusion/loss.py
+++ b/diffsynth/diffusion/loss.py
@@ -13,9 +13,16 @@ def FlowMatchSFTLoss(pipe: BasePipeline, **inputs):
     inputs["latents"] = pipe.scheduler.add_noise(inputs["input_latents"], noise, timestep)
     training_target = pipe.scheduler.training_target(inputs["input_latents"], noise, timestep)
     
+    if "first_frame_latents" in inputs:
+        inputs["latents"][:, :, 0:1] = inputs["first_frame_latents"]
+    
     models = {name: getattr(pipe, name) for name in pipe.in_iteration_models}
     noise_pred = pipe.model_fn(**models, **inputs, timestep=timestep)
     
+    if "first_frame_latents" in inputs:
+        noise_pred = noise_pred[:, :, 1:]
+        training_target = training_target[:, :, 1:]
+    
     loss = torch.nn.functional.mse_loss(noise_pred.float(), training_target.float())
     loss = loss * pipe.scheduler.training_weight(timestep)
     return loss