In view of strong coupling of thrust and trajectory characteristic of solid ramjet powered missile, a corresponding project trajectory optimization model was established, and an integrated method of genetic algorithm and sequence quadratic program was used for integrated trajectory missile optimum design which focuses on maximum range.The trajectory simulation result demonstrates that the range is improved by 21.7% while all flight condition and engine design constraints are met.The result also validates effectiveness of optimization method used by this article and necessity of integrated optimum design.