There are more than 3 specialized national defense patent agencies in China. For details, please inquire about the "national defense patent agency"
General agencies can't represent national defense patents. Because the contents of national defense patents involve state secrets, they are different from general patents when applying. The staff of general patent agencies are not managed according to the classified personnel, so naturally they can't go to them and reveal state secrets.
If you are a secret-related person, it is suggested that you go directly to the national defense patent agency to ask, so as to avoid breaking the law by leaking secrets.