Abstract: Aiming at the optimization problem of the position layout of the free route airspace entrance and exit, the definition model of the free route airspace boundary and the entrance and exit is established. As for the flight weighted distance deviation, the position optimization model under the given number of entrances and exits is established. The genetic algorithm based on elite retention is used to select a typical airspace in Europe for optimization analysis. The results show that after optimizing the position of the original entrance and exit of the airspace, the proportion of the weighted distance deviation of the flight in the large circular route is 5.412 6% lower than that of the actual flight. At the same time, the number of entrances and exits has an important influence on the weighted distance deviation of the flight. When the number of entrances and exits reaches 50% of the product of the number of starting and ending points outside the airspace, the flight effect of the large circular route can be achieved.