To continuously carry out a reversal processing for arranging the front and back of a paper sheet by one path without changing the order of the paper sheets in a paper sheet processing device.

Paper sheet are conveyed by a rotation on own axis of a pair of reversal rollers 33 at a predetermined position at the time of non-reversal conveying of the sheets while they are clamped between these reversal rollers 33. A whole of a pair of reversal rollers 33 is revolved at the time of reversal conveying of the sheets while the rotation on own axis of the respective reversal rollers 33 is stopped and the reversal rollers 33 are rotated on own axis in a reverse direction after the revolving is carried out by 180°.