The reentry trajectory of glide missile can be divided into three phases: descent and pull-up phase, glide phase and terminal phase. According the characteristics descent and pull-up phase, an optimization model of reentry trajectory was introduced, and the Gauss Pseudospectral Method was used to solve the optimization problem. Based on onboard trajectory optimization, the control command was obtained and updated onboard, and the closed-loop control trajectories were generated. The results show that the Gauss Pseudospectral Method works well with high precision and fast speed, and the presented closed-loop control can provide a missile capability of satisfying the desired objectives under various disturbances and uncertainties. 