In order to solve the problem of lack of theoretical basis for the order decision of aviation spare parts, this paper put forward the research on the order decision method of aviation spare parts by spare parts importance and inventory quota. This paper established an importance evaluation and inventory quota models by the fuzzy comprehensive evaluation method and the analytic hierarchy process and established 3 kinds of spare parts ordering models by using the importance, the importance level and the inventory quota of spare parts. The results show that the method can provide intelligent decision support for aviation spare parts ordering, and has high promotion and application value.