Advanced　small　modular　reactors　(SMRs)　use　different　design　in　the　systems,　structures,　components　from　large　reactors　for　achieving　a　high　level　of　safety　and　reliability.　In　present　work,　the　SMRs　severe　accident　caused　by　the　station　blackout　(SBO)　was　modeled　and　analyzed　using　MELCOR　code,　and　the　simulation　of　the　accident　scenario　response　to　SBO　was　conducted.　Based　on　the　steady　state　calculation,　which　agrees　well　with　designed　values,　we　introduced　the　SBO　accident　for　transient　calculation.　First,　the　case　of　the　SBO　accident　without　the　passive　core　cooling　system　(PXS)　was　calculated.　The　progression　and　scenario　in　the　reactor　pressure　vessel　(RPV)　and　the　containment　were　simulated　and　analyzed,　including　the　transient　response,　cooling　capacity　and　thermal-hydraulic　characteristics　and　so　on.　The　station　black-out　transient　in　the　SMR　can　be　simulated　accurately,　and　the　main　failure　model　in　the　accident　process　can　be　concluded.　Then　three　other　cases　of　the　SBO　accident　with　different　passive　safety　systems　(core　makeup　tank　(CMT),　accumulator　(ACC),　passive　residual　heat　removal　system　heat　exchanger　(PRHR　HX),　automatic　depressurization　system　(ADS))　of　the　PXS　were　calculated　respectively,　and　the　results　for　different　passive　safety　systems　were　compared.　The　passive　core　cooling　system　can　not　only　provide　water　to　the　primary　coolant　system,　but　also　take　away　the　reactor　decay　residual　heat.　So　in　a　station　black-out　transient,　we　can　get　more　time　for　restoring　AC　power,　and　effectively　prevent　the　accidents　such　as　Fukushima.　(C)　2015　Elsevier　Ltd.　All　rights　reserved.