Aiming at the large number of preparation work, a lot of operators and hard to organization of multi-aircrafts preparation, carry out optimal research on multi-aircrafts preparation. Based on analyze the single aircraft support group preparation process, establish multi-aircrafts preparation process math model, and introduce improved GA algorithm to solve the model. Combined with the example, separately use traditional GA and improved GA to carry out simulation calculation, and acquired the Gantt chart of preparation process. The simulation results show that the improved GA algorithm overcome the problems such as large computation intensity and large size of traditional GA, it can quickly converge and reduce time of aircraft preparation.