Abstract: In order to analyze whether the dynamics indices of 5 000-ton integrated heavy- haul train meet the safety requirements, this paper chose four lines near two electric power phases in Jinchang-Yushi section of Wujia section of Lanxin Railway for analysis. The paper used multi-body dynamics software, established a 5,000-ton freight train model, compared and analyzed the longitudinal, lateral and vertical dynamic performances of the train, and also analyzed the influence of train speed on safety index. The analysis results show that it is safe for 5000 ton heavy- haul train to run at a speed below 80 km/h in the key section of Lanxin Railway.