An intra-oral scanner includes an optical output unit； an optical output control unit configured to rotate the optical output unit along a first reference axis or moves the optical output unit so as to control an emission position of the output light； an optical system configured to reflect the output light with the emission position controlled by the optical output control unit to a tooth or teeth being scanned； an optical system driving unit configured to rotate the optical system along a second reference axis so as to control a reflection angle of the output light； a guide； an optical sensing unit configured to sense the light reflected by the optical system and convert the sensed light into an electrical signal； and a data transmitting unit configured to transmit information to a three-dimensional data generating unit to generate three-dimensional scanning model for the tooth or teeth being scanned.
