PGM (pragmatic general multicast) is a reliable multicast transport protocol, which runs on IP networks. Because PGM standard does not include any congestion control scheme in itself, it can’t achieve real-time response to satisfy the requirements of network and can’t timely adjust the sending rate. Based on the PGM protocol, a novel close-loop controller, which is suggested to be implemented between the sender and the CLR (current limiting receiver), is introduced in this paper to timely adjust the sending rate. The proposed rate control scheme brings the source’s sending rate of the network to be stable gradually and has fast response. Simulations are carried out for the proposed control scheme, and the simulation results demonstrate that the proposed algorithm has the following properties: scalability, stability, fast convergence, and fast response under various network environments. They show good performance of the proposed multicast control schemes.