感谢kmote，我找到了解决方案.

Thanks to kmote, I found the solution.

只需签入 SaveFormat 属性，如果该文档是模板(这里是此属性的可能值列表.

Just check in the SaveFormat property if the document is a Template (here is the list of possible values for this property).

Private Function isTemplate(ByVal Doc As Document) As Boolean
  Select Case Doc.SaveFormat
    Case wdFormatTemplate, wdFormatDocument97, _
         wdFormatXMLTemplate, wdFormatXMLTemplateMacroEnabled, _
         wdFormatFlatXMLTemplate, wdFormatFlatXMLTemplateMacroEnabled
      isTemplate = True
    Case Else
      isTemplate = False
  End Select
End Function