原始名称记载: Senju Metal Industry Co., Ltd.

A solder supplying method for maintaining the Bi content contained in a solder alloy in a solder bath at a predetermined amount even after soldering a large number of printed circuit boards with a Bi-containing solder alloy. A solder supplying method includes supplying an additionally supplied solder, which is Sn and/or a low-Bi solder alloy having a lower Bi content than a Bi-containing solder alloy, to a solder bath into which the Bi-containing solder alloy has been introduced, thereby adjusting the Bi content in the solder bath to the Bi content of the Bi-containing solder alloy when it has been initially introduced in the solder bath.