An experimental study was conducted on the pressure oxidation-cyanide leaching of cyanide tailings residue containing 8.75 g/t gold.Through mineralogical studies,it was found that the gold minerals in the cyanide tailings residue were fine-grained and mainly encapsulated by sulfide minerals,making it difficult to achieve ideal indicators through conventional cyanide leaching.Pressure oxidation pretreatment can address this issue,enabling effective gold recovery.The effects of slurry concentration,reaction pressure,reaction temperature,oxidation time,and grinding fineness on the pretreatment performance during pressure oxidation were studied through single-factor experiments.The results showed that under the optimal conditions of 12 % slurry concentration,3.2 MPa reaction pressure,220 ℃ reaction temperature,2.0 h oxidation time,and grinding fineness of -0.045 mm accounting for 95 %,the average gold leaching rate reached 90.75 %.