Abstract: A gold smelting company produces high concentration cyanide-containing wastewater during the detoxification process of cyanide tailings.Based on that,conventional Inco method is modified and copper salt precipitation method is developed.The test conditions are optimized.The optimal conditions are as follows:sodium pyrophosphate dosage 5.0 g/L,copper sulfate pentahydrate dosage 25 g/L,pH 6-8,reaction time 10-30 min.Under the conditions,the wastewater treated can meet the standard of the total cyanide mass concentration less than 10 mg/L in the circulating water.The method makes up for the shortcomings of conventional Inco method that it can not treat  cyanide-containing wastewater with high content of thiocyanate,realizes rapid and effective purification of cyanide-containing wastewater,with outstanding cyanide removal effect.The study provides technical support for detoxification of cyanide-containing wastewater.