Abstract: Under the environment model of grid method, the results of PSO algorithm are a set of discrete particles that is necessarily transformed into a continuous path by some guidelines. Aiming at the above problem, this paper proposes a new method to automatically transform the results of PSO algorithm to continuous path. In order to avoid the oscillating near obstacles in an artificial potential field method, this paper presents a method of mean filter to plan the shortest smooth path. Simulation results show that this algorithm can easily obtain the optimization path and effectively avoid the oscillation of the path.