A study on detoxifying,with ozone,the cyanide tailings slurry generated in the all-sliming cyanidation-CIP process at Guilaizhuang Gold Mine was conducted.The results show that under the conditions of pH 11.52 and ozone concentration of 7.14 g/m3 with the addition of 0.357 g/L,after 2 h of oxidation reaction,the mass concentration of total cyanide compounds in the leachate of the filter-press cake was reduced to 2.13 mg/L.In industrial production practice,the cyanide tailings slurry detoxification process with ozone mainly consists of feed slurry buffering,oxidation reaction,and stabilization treatment.The cyanide removal effect is good,with an ore treatment cost of 6.00 yuan/t,and no introduction of other interfering ions.The cyanide residue meets the standards for the disposal and pollution control  in tailings dam in HJ 943-2018 Technical specification for pollution control of cyanide leaching residue in gold industry.