Due to its comfort, convenience, safety and punctuality, high-speed train has become a prior intercity transportation way in China. The traction system, the core of the high-speed trains, is a complex electromechanical coupling system, whose reliability is of critical importance to the safety of the entire train. Along with the growth of running time, some components in the traction system degrade with age and may cause various kinds of faults. Thus, fault diagnosis and prognosis are urgently demanded in high-speed railway traction systems. The domestic and foreign development status of research and analysis for high-speed railway traction systems, including fault diagnosis, fault tolerant control and fault prognosis for the traction transformer, traction converter, traction motor, suspension system and tracking/braking unit are introduced. Furthermore, the basic ideas, research progresses and application conditions of each approach are discussed in details. Finally, some open problems and challenges in the area of fault diagnosis and prognosis of high-speed railway traction systems are also introduced.