The reason and effect of electric braking load asymmetry for the metro vehicle were analyzed based on the metro vehicle power composition and its electric braking character. By comparing the traditional network-based coordinating electric braking load distribution methods, a self-adaption distribution method was brought forward. The practicality of the method in engineering application was researched carefully. The method was validated by experiment and operation on real line. As a result, the technology of electric braking load distribution introduced in this paper could enhance the reliability, economy and comfort of metro vehicle significantly.