To enable the disconnected wiring part on an electronic circuit board to be easily corrected by a method wherein an infinitesimal metallic solution is fed to a disconnected part of a wiring on an electronic circuit board and then said solution is irradiated with laser beams for heating so as to form a conductive film for connecting the wiring disconnected part.

An infinitesimal metallic solution melted down with a solvent existent in air and substantially enclosed atmosphere or a vessel is shifted for feeding to the disconnected wiring part on an electronic circuit board 3 by a shifting means of a glass pipette 13 shifted by manipulater 15. The infinitesimal solution thus fed is irradiated with laser beams 8, 9 oscillated by an Ar laser oscillator 6 and YAG laser oscillator 7 for heating to form a conductive film for connecting to the disconnected wiring part. Through these procedures, the disconnected wiring part on the electronic circuit board 3 can be easily corrected.