diff --git a/Assets/Scripts/UI/UIBody3D.cs b/Assets/Scripts/UI/UIBody3D.cs
index 544bb8d3..d7703b82 100644
--- a/Assets/Scripts/UI/UIBody3D.cs
+++ b/Assets/Scripts/UI/UIBody3D.cs
@@ -48,13 +48,17 @@ namespace QFramework.Example
                             item.gameObject.SetActive(true);
                         }
                         index++;
+                        if (index >= bodys.Count)
+                        {
+                            index = bodys.Count - 1;
+                        }
                     }
                 }
             }
 
             public void Sub()
             {
-                if (index > 0)
+                if (index >= 0)
                 {
                     string name = bodys[index];
                     var body = root.subBody[name];
@@ -66,6 +70,10 @@ namespace QFramework.Example
                             item.gameObject.SetActive(false);
                         }
                         index--;
+                        if (index < 0)
+                        {
+                            index = 0;
+                        }
                     }
                 }
             }