The　Cu/solder　interfacial　stress　singularity　in　solder　joints　for　different　shapes　and　solder　materials　are　evaluated　based　on　the　theory　of　interfacial　mechanics.　The　interfacial　stresses　are　computed　by　the　finite　element　method　to　investigate　the　influence　of　solder　joint　shapes,　solder　materials　and　material　models　on　the　interfacial　stress　distribution.　Results　show　that　a　fatter　solder　shape　increases　the　interfacial　singularity,　and　the　singularity　of　Sn37Pb/Cu　interface　is　greater　than　those　of　Sn3.5Ag/Cu　and　Sn3.0Ag0.5Cu/Cu　interfaces.　Elastic-plastic　deformation　and　strain　effects　of　the　solder　under　drop/impact　loadings　reduce　the　interfacial　stresses.