Abstract: In an apparatus for controlling a rear angle of an outside mirror for an automobile, ultrasonic waves are, for a given period of time, projected onto: a controller (200) having coupling grooves (212, 212a, 212b) opposite to fixing grooves (211, 211a, 211b) for fixing the other end of inside cable (310) whose one end is fixed at a glass holder plate, and a supporting rod (220) with a predetermined length; and a control knob (100) having a coupling portion (110) with coupling projections (112, 112a, 112b) on its inside circumference, which correspond to the coupling grooves (212, 212a, 212b), for fixing the controller inserted, a supporting hole (113) with a predetermined length, where the supporting rod (220) is inserted into the inside of the coupling portion (110), and a hemispheric flange (120) having a guide hole (121) with a predetermined width, where a control case is inserted into the outside of the coupling portion (110), so that the coupling grooves (212, 212a, 212b) of the controller (200) are welded