To provide an image formation device capable of switching driving and stopping of a side surface delivery roller by a simple and inexpensive constitution without using a plurality of motors and a clutch mechanism.

A first gear 32 and a second gear 33 for transmitting drive force are connected to a drive input gear 31 fixed to a rotation shaft 30 of the side surface delivery roller 18a. The second gear 33 is an idle gear externally inserted slidably in a thrust direction relative to a central axis 34 and is urged in an arrow C' direction by a compression spring 35. The second gear 33 is selectively arranged at a first position where connection of the drive input gear 31 and the first gear 32 is released to shut off transmission of the drive force to the drive input gear 31 and a second position where it is connected to the drive input gear 31 and the first gear 32 to transmit the drive force to the drive input gear 31 by the urging force of the compression spring 35 and pressure-contact force of a projection part 36 projectedly provided on a paper delivery tray 19.