RMTP is a reliable multicast protocol based on local loss recovery through repair servers. A delay modeling analysis of RMTP is presented, which derives the expression of average delay between the initial arrival of a packet at a sender and its correct reception at a randomly chosen receiver. The analysis results indicate that the saturated value of RMTP delay performance decreases rapidly under more loss environment. With the increasing of the number of tail links served by per repair server, the saturated value of delay also decreases.However,with the increasing of the number of total tail links while keeping the number of tail links served by per repair server constant,the saturated value of delay hardly changes.Finally,the analysis is confirmed by simulation results.