High speed electric multiple units (EMU) train has been widely used in recent years at home and abroad. It is one of the most effective conveyances for passengers. The axle for high speed train is a very important part, which suffers from various loads of body and track，mainly including rotating bending and torsion loads. Ensuring the EMU axle with sufficient security, reliability and long service life raises very high demands for the axle material technology. Based on careful comparison of EMU axle technology at home and abroad, this paper discusses the process, chemical composition-microstructure-property relation, structure design etc., and forecasts the technological development of new generation axle for EMU with more than 400 km/h speed. At present, the axle steel for EMU with more than 400 km/h speed is being developed based on Materials Genome Initiative(MGI) technology in China.