The author argues that viewed over the long span of 300 years, the permanent settlement of Ming soldiers in the Guards and the Battalions of Yunnan served as a medium for implanting Ming administrative norms into local societies under the jurisdiction of native officials. His case study of the Lancang Guard demonstrates how the military functioned as intermediaries between the Ming state and native officials. The state relied on the Guards for maintaining stability in local society and for ensuring safety on strategic communication routes, while native officials relied on the Guards for aid in negotiating with the state and for protection of their own personal interests. This case study reveals the intricate relationship between the military, native officials and the state, and the spin off effect of the military on local society: the military promoted education and irrigation amongst ethnic peoples. The author’s findings put a fresh perspective on the military in Ming Yunnan, highlighting the Guards as focal points for promoting multi-faceted change in local society.