A mounting system for a laser diode enables adjustment of the location of the diode and of the direction of the diode's beam. Fine adjustments may be made of the location of the diode in side-to-side, up-and-down, and forward-and-back directions as well as rotationally for azimuth and tilt angle. A mounting fork is connected to a frame for movement side-to-side on the frame, with two spaced prongs of the fork extending generally vertically. A diode holder block containing the diode is positioned between the prongs and has cylindrical, generally arcuately convex vertical edges engaged between the generally planar surfaces of the forked prongs. This enables the block to be moved for adjustment by sliding and rotational manipulation up-and-down, forward-and-back, rotationally about a vertical axis for azimuth, and rotationally about a generally transverse horizontal axis for tilt.