An image output device comprising: a representative parallax acquisition unit; a provisional output parallax determination unit to determine a provisional output parallax for each of the stereoscopic image frames depending on an output condition of the stereoscopic video, based on the representative parallax for each of the stereoscopic image frames; an output parallax adjustment unit; and an output unit, wherein the provisional output parallax determination unit determines the provisional output parallax for a reference frame corresponding to the representative parallax for the reference frame, and determines the provisional output parallax for a target frame corresponding to the representative parallax for the target frame, in accordance with the provisional output parallax defined for each range of the representative parallax for the stereoscopic image frame, the reference frame being sequentially determined from the stereoscopic image frames, and the target frame being the stereoscopic image frame immediately after the reference frame.