How to choose the optimal trajectory is one of the most important problems in the UAV mission planning system when the UAV is applied to actual combat environment. In this dissertation, a twotarget trajectory optimization model with shortest total distance and minimum time balance is established in the effective inspection area, and then a trajectory planning based on the Chaos Genetic Algorithm is put forward. Taking advantage of the Logistic chaos sequence, this algorithm makes sure the cross and variation points of Genetic Algorithm, ensuring the precision of algorithm convergence, impairing buffeting problem generated by large crossintensity. The algorithm is applied to the experimental simulation of aeronautical planning in this dissertation. Simulation results showed that this method improved the precision of genetic algorithm.