QoS multicast routing problem is a nonlinear combination optimization problem

which is proved to be a NP complete problem.In order to fulfill the characteristics of real-time information transmission in next generation internet

a new quality of service（QoS） multicast routing algorithm based on asynchronous pattern particle swarm optimization（PSO） algorithm is proposed.It contains delay

delay jitter

bandwidth

packet loss and the least cost constraints.Network topology graph and fitness function are generated and designed first;secondly

restricted network model is put forward and PSO maximize fitness function is used to get the optimized Steiner tree.Simulation results show that the algorithm gives the better operation effect and the faster speed of convergence with compare to genetic algorithm and synchronous pattern PSO algorithm.