In　the　present　work,　the　effect　of　phosphorus　on　the　creep　fatigue　properties　of　Sn-Cu　eutectic　lead-free　solder　was　carried　out.　The　experimental　results　show　that　the　melting　temperature　was　almost　not　changed　with　adding　small　amount　of　P　element.　However,　the　addition　of　trace　P　element　led　to　the　decrease　in　the　property　of　creep　fatigue.　The　fractography　analysis　by　a　scanning　electron　microscopy　(SEM)　shows　that　ductile　fracture　was　the　dominant　failure　behavior　in　the　process　of　creep　fatigue　test　of　Sn0.7Cu　and　Sn0.7Cu0.005P　specimens.　It　should　be　pointed　out　that　there　is　significant　difference　in　the　fractographs　between　the　joints　of　Sn0.7Cu　solder　and　Sn0.7Cu0.005P　solder.　In　the　fractograph　of　Sn0.7Cu　solder　joint,　the　microstructure　is　prolonged　along　testing　direction,　and　the　dimples　were　more　than　the　fractograph　of　Sn0.7Cu0.005P　solder　joint.　In　addition,　the　voids　could　be　found　on　the　SnO.7CuO.005P　solder　joint,　and　trace　P　addition　may　increase　the　rate　of　forming　void　of　Sn0.7Cu　solder　joint.　The　voids　can　potentially　lead　to　crack　initiation　or　propagation　sites　in　the　solderjoint.　As　a　result,　the　creep　fatigue　of　solder　joint　containing　P　such　as　Sn0.7Cu0.005P　offers　worse　property　compared　to　Sn0.7Cu　solderjoint.　(C)　2009　Elsevier　B.V.　All　rights　reserved.