A stereo imaging apparatus includes: an imaging unit which generates an image; a stereo adapter which is mounted on the front of the imaging unit, and splits light from a subject into a first light flux and a second light flux along a parallax direction and guides the first and second light fluxes so that the first and second light fluxes are incident side by side on the imaging unit in a direction perpendicular to the parallax direction; and a stereo image generating unit which, based on the image, generates stereo images. The stereo image generating unit includes: a dividing unit which divides the image into two sub-images along the direction perpendicular to the parallax direction; a horizontal direction correcting unit which corrects any rotation of the subject in the two sub-images; and a trapezoidal distortion correcting unit which corrects any trapezoidal distortion of the subject in the two sub-images.