A sheet finisher of the invention includes: a fold unit that forms a fold line with a fold rollers; a roller unit that moves a first roller and a second roller along the fold line while pressing the fold line; a drive unit that moves the roller unit along the fold line from a standby position separate from an end of the sheet bundle; a drive motor that separates the first and the second rollers in a thickness direction at the standby position; and a nipping unit that places the sheet bundle on a first nip plate, and nips it by the first and the second nip plates. Both positions of the nip of the fold rollers and a nip of the first and second rollers are disposed to be substantially coincident with a position on an imaginary plane extending from a surface of the first nip plate.