The present invention relates to a carbon fiber carbonizing apparatus using a microwave, the carbonizing apparatus comprising: a carbonization furnace into which a microwave is radiated from an irradiation unit disposed in one side thereof; a moving pipe which is mounted to extend through the carbonization furnace and allows a carbon fiber to move along the inside thereof; and a heating body coupled to the outer circumferential surface of the moving pipe to absorb the microwave and thus generate heat, wherein at a location where the heating body is coupled to the moving pipe, one part of the moving pipe is covered by the heating body and the surface of the remaining part thereof is exposed.