In　the　present　work,　0.2 wt%　Ni　and　0.1–0.5 wt%　RE　(Ce　and　La　mixed　rare-earth)　were　added　into　Zn–20Sn　high-temperature　lead-free　solders.　The　effects　of　Ni　and　RE　additions　on　the　microstructure　and　properties　of　the　solder　alloys　were　investigated.　The　results　show　that　with　the　increase　of　RE　content,　the　solidus　temperature　of　the　solder　alloys　does　not　change　much,　but　the　liquidus　temperature　decreases,　and　the　wettability　and　microhardness　of　the　solder　alloys　increase.　Adding　Ni　or　RE　element　individually　does　not　change　the　IMC　layer　structure　at　the　solder/copper　interface,　but　it　affects　the　growth　of　the　IMC　layer.　That　is,　the　addition　of　Ni　inhibits　the　growth　of　the　interface　IMC　layer,　and　the　addition　of　RE　promotes　the　growth　of　the　IMC　layer.　©　2018,　Springer　Science+Business　Media,　LLC,　part　of　Springer　Nature.