If you want to find a patent agent, you can consult the local intellectual property office. In fact, there are patent agencies that accept national defense patent applications everywhere, such as Huazhong University of Science and Technology, Nanjing University of Science and Technology and Beijing Institute of Technology, all of which are qualified patent agencies.
Article 4 of the Patent Law of People's Republic of China (PRC) stipulates: "Where an invention-creation for which a patent is applied involves national security or vital interests and needs to be kept confidential, it shall be handled in accordance with the relevant provisions of the state." Refers to the application for a patent for invention involving national defense secrets that need to be kept confidential, and the patent acceptance organ is the national defense patent institution; Where an application for a patent for invention accepted by the patent administration department in the State Council involves national defense secrets and needs to be kept confidential, it shall be submitted to the national defense patent agency for examination, and the patent administration department in the State Council shall make a decision according to the examination opinions of the national defense patent agency.