Laser　crack-free　cutting　of　thick　and　dense　ceramics　(thickness　＞　10　mm,　relative　density　≥　98%)　by　single　pass　which　is　based　on　continuous　piercing　through　the　work-piece　was　presented　in　this　paper.　With　two　processing　stages　matching　with　appropriate　time　shot　for　every　piercing,　low　cycle　duty,　low　gas　pressure　and　other　processing　parameters,　the　crack-free　internal　straight　or　curve　shape　cutting　of　the　ceramics　could　be　obtained　by　CO2　laser　at　higher　cutting　speed　of　about　25-30　mm/min.　Combining　with　the　analysis　of　the　power　flowing　intensity　and　heat　accumulation　effects　around　laser　spot,　it　is　concluded　that　the　non-equilibrium　heat　accumulation　was　inhibited　effectively　by　the　single　pass　laser　crack-free　cutting　technique.　For　cutting　of　10　mm　thick　Al2O3　ceramic,　the　total　time　without　power　flowing　between　the　fore-piercing　and　the　next-piercing　by　the　technique　could　be　∼　600　ms,　which　combined　with　ejecting　of　melting　materials,　could　supply　enough　cooling　time　to　inhibit　the　non-equilibrium　heat　accumulation　resulting　in　cracks.