Defense discourse public relations is an important means for countries to showcase their strength and disseminate their values. It is particularly important to cultivate the ability of military personnel, especially cadets in military academies, to communicate defense discourse to the outside world.This paper discusses the training model of national defense discourse publicity ability based on corpus. This paper holds that the connotation of the ability of external publicity and translation of national defense discourse mainly includes security situation discourse, national defense policy discourse and national defense ideological discourse. Teachers can use the corpus to design teaching activities around the foreign language expression ability of these three kinds of discourse, through situational teaching method, task-driven method and other teaching methods, so as to effectively improve the students’ ability of national defense discourse communication.