Abstract: As the high complexity and low convergence speed, traditional methods could not solve QoS multicast routing problem to satisfy the network requirement. A Harmony Search algorithm based on Child-Node Encoding (CNE-HS) is proposed for better performance. Three improved aspects present as follows: a new method is designed to create initial solution and new solution, which improves convergence speed; a new dynamic method is proposed to change parameters, which accounts global searching and local searching ability; a new encode mechanism is designed based on children node, which accelerates improvising new solutions. Theoretical analysis and the results of simulations prove the low complexity of CNE-HS, and show that CNE-HS performs much better than GA and HS-based algorithm using Node Parent Index (HSNPI) algorithm in convergence speed and cost.