建立多级子菜单应该没什么问题。试试下面这个过程吧。
Sub testMenu()
Dim menug As AcadMenuGroup, pmenu As AcadPopupMenu, pmi As AcadPopupMenuItem
Set menug = ThisDrawing.Application.MenuGroups(0)
Set pmenu = menug.Menus.Add("Test0")
Set pmi = pmenu.AddSubMenu(0, "Test1").AddSubMenu(0, "Test2").AddSubMenu(0, "Test3").AddMenuItem(0, "Test4", "(princ ""Hello!"") ")
Call pmenu.InsertInMenuBar(0)
End Sub