In　order　to　solve　the　problem　of　cutting　temperature　measurement　during　the　QFN　cutting　separation　process,　the　infrared　thermal　imager　is　used　to　measure　the　QFN　cutting　temperature　under　different　conditions,　which　include:　with　cutting　fluid,　without　cutting　fluid,　and　different　cutting　speed　of　300/600/900　rpm.　Temperature　measuring　results　show:　when　without　cutting　fluid,　temperature　almost　not　influenced　by　cutting　speed,　EMC　highest　temperature　basic　maintain　at　80　degrees　C,　copper　lead　frame　highest　temperature　at　127　degrees　C;　When　with　cutting　fluid,　the　highest　temperature　of　EMC　rise　from　23　degrees　C　to　35　degrees　C,　the　highest　temperature　of　copper　lead　frame　rise　from　35　degrees　C　to　40　degrees　C.　The　temperature　of　copper　lead　frame　is　higher　than　EMC.　The　simulation　results　show　that　the　maximum　stress　of　copper　layer　is　greater　than　the　EMC　layer,　joining　cutting　fluid　can　effectively　reduce　the　stress　value.