In　this　paper,　the　effects　of　rare　earth　(RE)　element　additions　on　the　mechanical　creep-fatigue　property　of　the　Sn3.8Ag0.7Cu　solder　joint　have　been　investigated.　The　results　show　that　adding　a　small　amount　of　the　RE　elements　can　evidently　increase　the　creep-fatigue　rupture　lifetime　of　the　Sn3.8Ag0.7Cu　solder　joint.　The　increase　in　the　creep-fatigue　property　can　be　attributed　to　the　reduction　of　the　creep-fatigue　damages　and　the　change　of　microcrack　propagation　site　during　the　fracture　process,　which　depends　on　the　refining　of　intermetallic　compounds　due　to　the　RE　elements.　In　addition,　it　is　also　found　that　adding　the　RE　elements　decreases　the　strain　amplitude　of　the　solder　joint　under　the　constant　stress　amplitude.　(C)　2008　Elsevier　B.V.　All　rights　reserved.