A lead-free solder ball is provided which suppresses interfacial peeling in a bonding interface of a solder ball, fusion defects which develop between the solder ball and solder paste, and which can be used both with Ni electrodes plated with Au or the like and Cu electrodes having a water-soluble preflux applied atop Cu. The lead-free solder ball for electrodes of BGAs or CSPs consists of 1.6-2.9 mass % of Ag, 0.7-0.8 mass % of Cu, 0.05-0.08 mass % of Ni, at least one of Fe and Co in a total amount of 0.003-0.1 mass %, and a remainder of Sn.