Abstract: Transient stability analysis is an important part of power system stability, which highly determines the effectiveness and rationality of power system such as system planning and operating. At present, the bottleneck of improving the reliability of transient stability analysis lies in the load model. Although lots of new practical load models have been presented recently, some characteristics, especially for load shedding under transient voltage sink, has not been considered in transient stability analysis. In order to verify the influence of load shedding characteristic under transient voltage sink in transient stability analysis, with the CEPRI-36 system as example, the influence of different load models under different situations in transient stability simulation are studied. The research shows that the load model and the load shedding characteristic under transient voltage sink both have great effect on simulation results, and this kind of characteristics should be considered in transient stability analysis.