Abstract: A gold concentrate from Xinjiang contains 37.10 g/t Au,3.08 % As,15.17 % Fe,and 13.00 % S.The native gold mainly exists in the form of microfine-particle gold,which accounts for 91.04 %.The gold leaching rate of the gold concentrate,a typical arsenic-containing microfine-particle refractory gold concentrate,is only 29.16 % by direct cyanide leaching.According to the characteristics of this gold concentrate,systematic biological oxidation single tank experiment and continuous experiment were carried out.The results showed that under the condition that the grinding fineness of -0.045 mm accounts for 90.00 %,the bacteria species HYBBSX-Z1212-TL cultivated by Changchun Gold Research Institute Co.,Ltd.,oxidation slurry concentration is 18 % and continuous oxidation lasts for 6 d,the oxidation rates of As,Fe and S on the gold concentrate are 96.84 %,93.83 % and 74.97 % respectively;when the gold in oxidation slag is recovered by cyanidation CIL gold extraction process,the optimal conditions for cyanidation is that the slurry concentration is 33 %,the calcium oxide dosage 15 kg/t,alkali treatment time is 2 h,the sodium cyanide dosage is 20 kg/t,the cyanide leaching time is 48 h，the gold leaching rate is 94.11 %.