To provide an added alloy for nonlead solder high in wettability and very high in joinability with a lead wire or the like composing an electronic circuit by adding it to a melting solder vessel.

This alloy is an added alloy for nonlead solder charged and diffused in melting nonlead solder mainly consisting of Sn and contg. 0.1-10 wt.% Ni and the balance Sn. The content of Ni is preferably made to 1-3 wt.%. Further, one or plural components selected out of a group composed of Ge, Ga or P are added respectively by 0.1-5 wt.%. The Ge, Ga or P are preferably made within a range of 0.1-1 wt.%.