A　numerical　simulation　was　studied　on　temperature　field　in　ceramics　by　using　finite　difference　method　(FDM)　during　laser　sintering.　The　heat　conduction　equations　were　presented,　then　the　boundary　condition　was　given.　The　mathematical　model　of　laser　sintering　on　ceramics　was　established　and　the　equations　were　solved　by　FDM.　The　change　of　temperature　field　in　ceramics　was　described　by　simulation　program.　The　effect　of　technological　conditions　on　temperature　field　in　ceramics　was　analyzed.　It　shows　that　the　lengthways　temperature　gradient　in　ceramics　is　only　relevant　to　the　laser　power,　while　the　transverse　temperature　gradient　in　ceramics　is　relevant　to　the　laser　speckle　radius　and　the　transverse　intensity　distribution　of　laser.