To feed paper only by driving a driving means of a sheet feeding unit for feeding the sheet.

The sheet feeder 69 is formed such that a plurality of sheet feeding units capable of feeding stored sheet to a device body of an image formation device to the device body in series. Option feeding cassette 57, 58, 59 are provided with a sheet feeding mechanism 94 for feeding out the stored sheet; a sheet conveying mechanism 95 for conveying the fed out sheet; a motor 71 for driving both mechanisms 94, 95; and a one-way gear 80 for transmitting operation of the sheet conveying mechanism in the sheet feeding cassette on an upstream side in the sheet conveying direction to the sheet conveying mechanism of the option feeding cassette on a downstream side. Power consumption and noise are suppressed to a low degree only by driving the motor of the option feeding cassette for feeding the sheet.