In this paper,on the basis of review of trajectory optimization method at home and abroad,the direct method and sequential quadratic programming algorithm is used to solve the trajectory optimization problem.The trajectory optimization problem is transformed into a parameter optimization problem using direct method and the parameter optimization problem is solved using sequential quadratic programming.A trajectory optimization algorithm is written using C++,and a numerical simulation of maximum range entry trajectory is performed.The simulation results show that the technology of trajectory optimization for lift reentry vehicle proposed in this paper is reasonable and feasible with good results.