Abstract: In Xiajadian gold mine, the particle size of -0.037 mm is 60%, the content of iron sulfide mineral is low 1%, and the cyanide residue is mainly free cyanide. In order to make the cyanide content in the cyanide-broken tailings meet the requirement of backfill utilization, a comparative test on the cyanide-broken effects of solid-liquid separation washing, hydrogen peroxide oxidation and ozone oxidation was carried out according to the characteristics of the cyanide-containing tailings of Xiajiadian gold mine. The results showed that the three methods of cyanide breaking effect is good or bad in order: ozone oxidation > hydrogen peroxide oxidation >lid-liquid separation washing method. When the pH value of cyanide-containing tailing pulp is adjusted to 8, the ozone concentration is 35.1 mg/L, ozone flow rate is 1 L/min, and cyanide-breaking time is 45 min, the total cyanide-containing content of tailings can be reduced from 10 mg/kg to 0.88 mg/kg, and the toxicity index of tailings can meet the requirements of standard backfill utilization.