Based on the analysis of timeslot synchronous process in the upstream channel for HFC network ,the mathematical model is built for the process of timeslot synchronous in the upstream channel, while the system is undergoing fault recovery. The paper emphasizes on the analysis of the average time in which the HFC network can complete the timeslot synchronous in the upstream channel. The experimental results under different conditions, such as network scale, parameter value of competition resolution algorithm and bandwidth allocating scheme for the upstream channel are given, and the optimizing methods are proposed.