To provide a bicycle suitable for little children or for folding operation in which the height of a saddle can be adjusted in a wide range, and the saddle is provided at a low position.

A saddle supporting part is formed by telescopically arranging at least three hollow members of different inside diameters. The saddle supporting part has a holder to fix the saddle at an arbitrary position. The height of the saddle can be adjusted in a wide range, and the saddle can be provided at a low position.