This study, in an attempts to contribute to the studies of military English as well as its pedagogy, selects and analyzes a genre of military English. The military genre, naval unit introductions, concerns the missions, history and capabilities of a naval unit with authentic use of language along with navy conventions, and thus is a good example of genre analysis. The results of analysis reveal not only the communicative purposes of the genre, but also the rhetorical structure and its distinctive use of language. To achieve the communicative purposes of introducing a unit, the rhetorical moves in the genre are structured from an identifying move through a move of historical events to a move of significance. Along with this structure, the uses of content words, voice, tense, and pronouns cooperate with each other to contribute to the overall communicative purposes. This study is significant in that this broadens the scope of English for Specific Purposes studies to cover military English, and provides the qualitative evidence for future studies and pedagogy for military English. In particular, the findings can be exploited in the teaching of naval unit introductions for military communication, and distinctive use of language and rhetorical structure of American naval unit introductions can immediately contribute to the learners understanding of a particular military genre, and possibly military English in the navy.