An optical tomographic imaging apparatus includes a measurement light optical path length changing unit configured to change an optical path length of measurement light. In a case where any one of a plurality of imaging regions of an object (for example, a region of an anterior eye of a subject's eye and a region of a fundus of the subject's eye) is selected, the optical tomographic imaging apparatus can control the measurement light optical path length changing unit according to a size of an imaging range of a tomographic image corresponding to the selected imaging region.