Abstract: Biological oxidation gold extraction process is a veryeffective pretreatment technology forrafractory gold ores which possess the advantages of low pollution and high leaching rate.The project focus on solving problems that produce when using biological oxidation gold extraction process in high latitude of extremely low temperature environment (the annual average temperature of the project place is -0.6℃,the lowest temperature is -47℃).Finally,the engineering of the project achieves good effect by the research of strain release,oxidation series distribution,settlement and the technology of defoaming.The gold recovery increases from 76.67% to 92.48%.