An optical guide end-fire coupling apparatus including a light source section having a condenser lens system for converging a laser beam to be incident on an optical guide, having a first light incident end facet, of an optical guide device, having a second light incident end facet, and including an actuator for finely adjusting the position of the condenser lens system with respect to an optical, i.e. a z axis of the condenser lens system, an x axis and a y axis, which axes are all orthogonal with each other and a photodetector assembly for detecting a light intensity of a return beam of a laser beam which is emitted from the light source section and reflected by the second light incident end facet on which the first light incident end facet of the optical guide is facing, and for controlling the actuator in accordance with the detected light intensity so that the position of the actuator is adjusted with respect to the x, y and z axes.