Abstract: The national defense discourse of press conference is one of the most important of the discursive type. This corpusbased study examines from the rhetorical perspective the use of rhetorical rational appeals in the discourse of press conference of Chinese Ministry of Defense(MOD), and elaborates on how the institutional rhetor, by catering to different types of topics and argumentative and rhetorical agents, employs fitting rhetorical strategies and a persuasive trichotomy of “Emphasize us, unite friends, deemphasize opponents” by following the discursive guideline of “on just ground, to our advantage and with restraint”to achieve identification by sympathy and identification by antithesis. It also further demonstrates the importance of rhetoric to defense discourse studies and the feasibility of corpus-based empirical rhetorical research.