AbstractTrack composite irregularity is the source of violent harassment of the wheel-rail system. They cause a vibration, and the track irregularity has the significant impact on train's driving security, stability, the life of track component and the vehicles as well as the environmental noise. At present, the key point of the Chinese railways’ developments is high speed, heavy haul and shortcut transportation, thus the influence of rail failure and track composite irregularity will be more remarkable, which has become a primary factor that limits running speed. This paper analyzes the characters and mechanism of the track irregularity come into being, forecasts the trend of track irregularity development and explores the hidden risks which possibly occur and influence the safety of railway traffic.