Abstract: The mass concentration of arsenic in waste acid produced with copper smelting fume is 3.0-10.0 g/L,copper 0.1-3.5 g/L,and acidity 60-120 g/L.The test investigated the arsenic removal effect of different vulcanizing agents,chose iron matte to treat copper smelting waste acid,optimized the influencing factors and obtained the optimal treatment process.The results show that with iron matte grinding fineness -74 μm accounting for over 80 %,the dosage 1.2 times the theoretical dosage of electrolysis plating copper and arsenic and reaction time 2 h,the treated copper smelting waste acid has an arsenic mass concentration lower than 0.03 g/L.The arsenic removal rate can be over 99.5 % and the reaction rate is controllable without introducing other impurities,which can satisfy the demand of arsenic removal from copper smelting waste acid.