PURPOSE: To obtain a laser diode protecting tool so as to dispense with a protective circuit or a protective device.

CONSTITUTION: A protecting tool is formed through such a manner that a flat conductive soft part 11 of anisotropic conductive rubber which limits the conduction of current to a certain direction and a conductive face member 12 of aluminum or the like fixed to the upper surface of the flat conductive soft part 11 into one piece. The electrodes 6A to 6C of a printed board electrically connected to the anodes and cathodes of a laser diode are short-circuited with the conductive soft part 11, so that the laser diode is protected against electrostatic discharge failure. The resistors Rs of the conductive soft part 11 are gradually decreased in resistance with an increase in pressure applied to the protecting tool, so that a surge current is prevented from flowing through the laser diode even if static electricity occurs on an operator who carries out a short-circuit operation.