Abstract: Based on particle swarm optimization(PSO) algorithm,an approach is presented to solve the drilling path planning problem in discrete space.In order to meet the needs of integer coding in drilling path planning,a duality conversion method and an operating mode for the operator elements are established to improve the operator of the algorithm.As for the problem of low global convergence rate in standard PSO,a method based on mathematical model is introduced to regenerate the stop evolution particles and to improve the algorithm.Experiment indicates that the global convergence rate of the improved PSO is increased more than 3 times over that of the standard PSO,and that the improved algorithm has the characteristics of easy realization,fast convergence speed and better global convergence capability.In practical applications,the new PSO is used to optimize the drilling path,and the time spent on moving the worktable is saved by 17.9%.