选中以后，Ribbon菜单上没有删除么？权限不够吧？

没有删除，只有编辑，最高权限了。
 好像Project是故意設計成不容易刪東西的(即使你是PM)

不知道這是不是你要的步驟:

To delete resources and users:
1.On the Project Web App home page, on the Settings menu, click PWA Settings.
2.On the Server Settings page, in the Queue and Database Administration section, click Delete Enterprise Objects.
3.On the Delete Enterprise Objects page, select the Resources and Users option.
4.Select the user or resource that you want to delete.
5.Click Delete.
6.On the confirmation dialog box, click OK.