Of　late,　given　the　difficulties　in　gold　extraction　and　severe　environmental　pollution　emanating　from　cyanide　extraction　of　Carlin-type　gold　concentrate　(CTGC),　a　novel　pressure　oxidation　pretreatment　followed　by　sodium　jarosite　decomposition　and　fine　grinding　was　first　proposed　to　extract　gold　from　the　CTGC　in　a　non-cyanide　system.　Thermodynamic　computations　of　the　Gibbs　free　energy　and　the　Eh-pH　diagram　of　different　reaction　systems　were　calculated　to　reveal　the　reaction　mechanism　during　the　treatment　process.　The　optimal　pressure　oxidation　pretreatment　conditions　were　determined　as　follows:　stirring　speed　600　r/min,　liquid-to-solid　ratio　of　4,　pH　1.2-1.3,　partial　pressure　of　oxygen　1200　kPa,　temperature　225　degrees　C,　and　time　1.5　h.　The　extraction　of　gold　increased　from　9.7　to　82.1%.　The　sulfur　conversion　mechanism　and　the　distribution　of　the　gold　phase　as　a　function　of　leaching　temperature　during　the　pressure　oxidation　leaching　process　were　investigated.　The　precise　regulation　and　control　mechanism　of　sodium　jarosite　decomposition　and　fine　grinding　were　clarified.　Furthermore,　the　polysulfide　leaching　results　show　that　pressure　oxidation　leaching　of　the　CTGC　followed　by　sodium　jarosite　decomposition　and　fine　grinding　can　efficiently　liberate　gold　from　the　mineral　envelope　and　provide　favorable　conditions　for　gold　extraction　in　a　non-cyanide　leaching　system.　The　leaching　efficiency　of　gold　in　the　poly-sulfide　system　reached　96.8%.　This　process　has　proved　to　be　a　promising　alternative　for　efficient　and　environmentally　friendly　extraction　of　gold　from　the　refractory　gold　ore.　[GRAPHICS]　.