To provide an auxiliary device for a wheelchair allowing a user of the wheelchair to change over a traveling state in the seated state on the wheelchair and to provide the wheelchair equipped therewith in a simple constitution and to provide the auxiliary device for the wheelchair easily attached without remodeling the existing wheelchair and to provide the wheelchair equipped therewith.

A guide member vertically movably supporting a second auxiliary wheel and a lever engaged with an auxiliary wheel support member and a frame of the wheelchair are provided, so that a large wheel is lifted by a small force by the principle of the lever.