An original transporting device includes: an original placing portion; an original discharging portion; a first transport path that connects the original placing portion and the original discharging portion; a second transport path that is branched from the first transport path and is connected to a switchback transport path; a changeover unit that changes over a transport route along which an original is transported to either one of the first transport path and the second transport path; a first detecting unit that detects the presence or absence of the original; a first determining unit that determines whether or not the original is a final page original based on the detection; and a controlling unit that controls a transporting unit and the changeover unit so as to discharge at least a portion of the final page original to outside the device through the second transport path based on the determination.