Abstract: A 3D-image oral scanner with a stereo optical system configured using a single camera according to the present disclosure includes a stereo image optical unit 3-dimensionally photographing measurement objects in an oral cavity through one camera, wherein the stereo image optical unit includes: a first light path changer changing paths of a first light image and a second light image traveling inside at different angles after reflecting from a measurement object in an oral cavity to an image light path; and one camera sensor taking the first light image and the second light image together that have traveled inside at different angles and of which the paths have been changed by the light path changer.