The　behavior　of　the　balcony　spill　plume　is　important　for　the　smoke　management　design　but　yet　not　well　understood　now.　Further　study　on　balcony　spill　plumes　is　needed.　The　behavior　of　the　balcony　spill　plume　will　be　studied　by　computational　fluid　dynamics　(CFD)　in　this　paper.　Five　existing　plume　models　will　be　reexamined　with　the　numerical　results.　The　results　show　that　entrainment　coefficient　of　0.11　is　much　better　in　describing　the　entrainment　behavior.　The　results　would　be　useful　for　the　smoke　management　system　design　in　atrium　and　also　can　give　some　good　suggestion　for　the　existing　fire　codes　revision.