Distributed routing can find multicast tree and adapt to dynamic changes of multicast members in case of acknowledge local network state. Majority of current distributed multicast routing algorithms based on the shortest delay, which can achieve load balance large additional overhead. The paper presented a kind of load balance multicast routing algorithm based on distributed computation and centralized control. It reside computation Agent in each node to compute forward probability and to maintain node routing table, node state table and forwarding probability table. In addition, it can detect delay of adjacent nodes and coordinate session establishment based on the copy, parameter transmission and notification of control Agent. On this basis, the algorithm achieved dynamically joins and leave session of multicast members. Algorithm analysis results show that the algorithm can improve the overall efficiency of network transmission.