A laser eraser and microwelder capable of operating with a pulsed or continuous-wave laser radiation is described. The device comprises a laser generator, a miniaturized electric power supply unit and a laser working head connected to the power supply unit through a flexible lasing fiber optics accompanied by an electric cable. The lasing fiber optics is optically coupled to said laser generator for generating and transmitting a laser radiation to the laser working head, and the cable conducts the laser triggering current to the laser generator through a triggering switch located in the laser working head. As an eraser, the device utilizes a defocused laser beam to erase an error character by vaporizing it from written matter and can be used either on a desk top or on a typewritter by attaching the power supply unit to the side of the typewriter housing. As a microwelder, the device utilizes a focused laser beam to weld miniaturized parts, components, and circuit leads. Radiation safety is achieved by providing a safety means in the laser working head which must be placed on the workpiece and manipulated before the triggering switch can be actuated to energize said laser generator.