To improve the order picking efficiency and shorten storage time in Automatic Storage & Retrieval System (AS/RS), a mathematical model was constructed to solve the problem of picking path optimization.According to the operation character of the order picking of fixed shelf storage area in a single roadway, an hybrid particle swarm algorithm combined with simulated annealing algorithm was presented.In the solution process, particle swarm optimization (PSO) was used to initialize the swarm, so as to improve the searching performance of the algorithm and optimize the results.The method can improve the optimization efficiency and shorten the searching time.In the iterative process, the simulated annealing algorithm was used to avoid premature convergence and to prevent from getting into local optimum as in the conventional PSO due to its probabilistic jumping ability.The examples show that compared with the standard PSO, the algorithm has the merits of shorter calculation time, faster convergence and fewer times of iterations.