In the course of carrier aircrafts landingthe officer must arrange a safe and efficient landing sequence according to such uncertain factors as the flight states of the aircrafts and the external conditions.The paper mainly focuses on the carrier aircraft landing sequencing problem.Besides the influence of various factors on the landing sequencethe influence of failed landing is also taken into consideration.An optimal mathematical model taking the reducing of delay time and delay cost as its objective is built.Considering the deficiency of the traditional genetic algorithman improved genetic algorithm is proposed and used to solve the model.Simulation result shows thatthe optimized landing sequence can effectively reduce the delay time and delay costand thereby improve the utilization rate of the carrier deck.