Abstract: Biooxidation pretreatment process is used in refractory gold ores.The optimum temperature for bacteria is 40 ℃-44 ℃.Bacteria are sensitive to ambient temperature.The growth of bacteria and the oxidation rate of sulphide would be impacted in low temperature,while the bioactivity of bacteria is  deactivated or even to death in high temperature.The cooling system or heating sytem is set in bioxidation process to keep the optimum temperature for bacteria and the oxidation rate.The paper takes the production practice of BIOX-biooxidation process in Jinfeng Mining Company,introduces the flowsheet and principle of BIOX process,analyzes the influence of temperature and control measures,summarizes the temperature variation in recent years for BIOX-biooxidation process,analyzes the reason for temperature rise,and proposes the methods for cleaning the scaling in cooling system and lowering temperature.The study provides reference for other gold producers to control the temperature in the biooxidation process.