diff --git a/comfy/ldm/trellis2/model.py b/comfy/ldm/trellis2/model.py
index fc8df3c2b..1c5d6c3ec 100644
--- a/comfy/ldm/trellis2/model.py
+++ b/comfy/ldm/trellis2/model.py
@@ -862,12 +862,12 @@ class Trellis2(nn.Module):
             out = self.shape2txt(x_st, t_eval, c_eval)
         else: # structure
             orig_bsz = x.shape[0]
-            if shape_rule:
+            if shape_rule and orig_bsz > 1:
                 half = orig_bsz // 2
                 x = x[half:]
                 timestep = timestep[half:] if timestep.shape[0] > 1 else timestep
-            out = self.structure_model(x, timestep, context if not shape_rule else cond)
-            if shape_rule:
+            out = self.structure_model(x, timestep, cond if shape_rule and orig_bsz > 1 else context)
+            if shape_rule and orig_bsz > 1:
                 out = out.repeat(2, 1, 1, 1, 1)
 
         if not_struct_mode: