Accidents　of　chemical　dangerous　goods　(CDG)　are　the　typical　public　emergencies.　In　recent　years,　the　accident　rate　has　shown　a　clear　upward　trend.　In　order　to　prevent　or　reduce　accidents,　this　paper　carries　out　the　study　on　the　public　management　capability　of　CDG　accidents.　By　taking　Jinan　City　as　an　example,　the　fuzzy　analytic　hierarchy　process　(AHP)　was　used　to　evaluate　the　public　management　capacity　of　CDG　accidents.　Then,　the　ArcGIS-based　public　management　capability　decision　support　system　of　chemical　dangerous　goods　was　constructed,　to　simulate　the　ammonia　leakage　accident　and　analyse　the　emergency　evacuation　module.　The　research　results　show　that:　75.3%　of　the　experts　believe　that　the　public　management　capacity　of　CDG　accidents　in　Jinan　City　is　in　a　good　or　general　state,　and　more　attention　has　been　paid　to　the　crisis　prevention　and　early　warning　ability　before　the　accident;　the　system　estimates　the　evacuation　area,　the　evacuation　personnel　(38,792　people)　and　the　best　route　for　evacuation　(1,536.84195458m　long)　after　instantaneous　rupture　of　15t　ammonia　transport　vehicle.　This　study　has　certain　practical　significance　for　preventing　and　reducing　the　casualties　of　people　and　property　caused　by　CDG　accidents.　©　2018,　AIDIC　Servizi　S.r.l.