There　have　been　numerous　studies　on　extinguishing　room　fires　by　water　mist　fire　suppression　system　(WMFSS)　in　the　past　decade.　Interactions　between　the　fire-induced　flow　and　the　discharging　water　mists　were　studied.　Carrying　out　experiments　with　physical　models　to　understand　more　on　the　physics　of　experiment　is　expensive.　Therefore,　well-validated　numerical　models　by　fire　tests　are　also　required.　These　models　are　commonly　used　as　an　engineering　tool　for　designing　water　mist　fire　suppression　system.　In　addition　to　taking　the　room　as　a　homogeneous　zone,　two-layer　zone　approach　is　also　used.　Results　based　on　these　approaches　were　applied　to　evaluate　the　performance　of　water　mist　system.　The　application,　advantages,　limitations,　and　key　results　of　the　theories　on　predicting　the　performance　of　water　mist　fire　suppression　system　will　be　reviewed　in　this　article.　©　2004,　Baywood　Publishing　Co.,　Inc.