To provide a footrest structure of a motor-driven wheelchair capable of widening the moving range of the motor-driven wheelchair by attaining traveling over a step without being influenced by the diameter of the front wheels of the motor-driven wheelchair.

This footrest structure is provided with a vertical movement function part 6 for advancing a footrest 5 downwards to a motor-driven wheelchair body 2, grounding the footrest 5 on the step A, advancing the footrest 5 further downwards, floating a caster wheel 4 and enabling the caster wheel 4 to go over the step A.