For　real　solder　joints　used　in　electronic　devices,　EM　and　creep　may　be　two　relevant　reliability　problems　because　solder　joints　usually　serves　under　a　combination　of　current　stressing,　elevated　temperatures,　and　mechanical　loading　conditions.　Especially　when　the　size　of　solder　joints　scales　down　and　current　density　escalates,　EM-induced　microstructure　change　should　have　certain　impact　on　creep　behavior.　In　this　study,　we　analyzed　and　discussed　how　EM　influenced　the　creep　behavior　of　lead-free　solder　joint　from　the　perspective　of　EM-induced　IMCs　change.　Behaviors　of　both　interfacial　and　matrix　IMCs　were　observed　and　attempt　to　reveal　the　roles　they　played　in　the　failure　of　real　lead-free　solder　joint.　From　this　study　we　can　conclude　that:　during　EM,　grain　size　of　interfacial　IMCs　at　both　sides　was　increased,　and　the　size　at　anode　side　was　much　larger.　The　shape　of　interfacial　IMCs　was　changed　from　scallop　shape　to　hexagonal　prism.　Besides,　there　were　many　Cu6Sn5　migrated　into　solder　matrix.　During　creep,　pre-EM　process　alleviated　deformation　of　solder　matrix　and　brought　about　brittle　fracture　of　a　solder　joint.　©　2014　IEEE.