Abstract: The gold in a gold ore is dominated by encased gold in sulfide minerals,accounting for 55.71 %,followed by exposed gold.Exposed gold is mainly associated gold and dissociated gold is rarely seen.According to the ore property,the study compared all-sliming cyanidation leaching and pretreament-cyanidation leaching processes,mainly investigating 3 pretreatment processes namely roasting oxidation,acidic pressure oxidation,alkaline atmospheric pressure heating oxidation.The results show that the gold leaching rate by all-sliming cyanidation leaching is only 29.2 %,and higher gold leaching rate can be obtained by pretreatment-cyanidation leaching;compared to the other 2 pretreatment processes,roasting oxidation pretreatment process has a better comprehensive effect and the gold leaching rate of roasting oxidation-fine grinding-cyanidation leaching process is 90.8 %.