A photographic paper reserver mechanism disposed between a printing unit and a development unit and adapted for absorbing the difference between the processing speeds of the printing unit and the development unit. This photographic paper reserver mechanism is provided with a flap which is movable between a first position at which the flap guides the leading end of the photographic paper supplied from the first roller so that this leading end is received by the second roller and a second position at which the flap allows the photographic paper received by said second roller to be bent and suspended between the first and second rollers, and at least one guide arm which forms, between itself and the flap, a path through which the photographic paper is transported to the second roller when the flap is in the first position, and which is interposed between the first and second rollers so as to prevent the photographic paper from moving straight to the second roller when the flap is in the second position. The photographic paper can be guided from the first roller to the second roller while being positively curved and suspended.