Electromigration　(EM)　behavior　of　eutectic　SnBi　solder　joint　was　investigated　with　current　density　of　5x10(3)　A/cm(2)　at　room　temperature　and　high　temperature　(100　degrees　C).　Results　indicate　that　the　Bi　atoms　were　extruded　out　of　the　anode　interface　and　cracks　were　formed　at　the　cathode　interface　after　465　h　current　stressing　at　room　temperature.　However,　the　microstructure　of　eutectic　SnBi　solder　joint　changed　much　at　high　temperature　after　115　h　current　stressing.　Cu3Sn,　Cu6Sn5　and　Bi　layers　were　formed　at　the　anode　in　sequence,　and　the　crack　propagated　through　the　whole　cathode　interface.　Solder　depletion　at　the　cathode　was　accelerated　after　applying　such　a　high　temperature,　leading　to　higher　current　density　in　some　local　regions　which　could　produce　much　more　Joule　heating　and　finally　induce　the　melting.　At　molten　state,　Sn　reacted　with　Cu　to　form　a　number　of　Cu6Sn5　bumps　in　the　central　solder　matrix　which　reduced　the　reliability　of　the　solder　joint.