To provide a folding bicycle to be folded and assembled in a short period of time and compactly with the front and rear wheels being at the same position when folded.

In the folding bicycle with a caster, a standing pipe 1 on the rear wheel 11 side and a front pipe 2 on the front wheel 14 side are connected with support pipes 3, and the support pipes 3 in the linear state can be bent with a fulcrum 6 in the support pipes 3 as the axis. The caster is attached to the lower end of the standing pipe 1. The fulcrum 6 is located at such a position as divides the distance between a wheel shaft 14a of the front wheel 14 and a wheel shaft 11a of the rear wheel 11 into two equal parts when the front wheel 14 is rotated by 180 degrees.