A roll paper holder includes: a blade member having a blade provided at an end of a base, a press projection provided at the other end of the base, and a convex portion provided on an upper surface of the base; a blade-member-storing case pivotally supporting the convex portion of the blade member; and a holder body to which a roll paper is attachable, in which the blade-member-storing case is mounted on an upper surface of the holder body with a base end pivotally supported by the holder body, and the blade-member-storing case has a cutout in a side thereof, the cutout being curved from a front end of the side to a lower portion of the side close to the base end of the blade-member-storing case.