Abstract: One-time electrolysis is used to refine 4N copper in Zijinshan Gold-Copper Mine to prepare 5N high purity copper and the influence of current density,electrode space and electrolyte temperature on 5N high purity copper is investigated.The results show that one-time electrolysis can produce 5N high purity copper with purity over 99.999 8 % in sulfuric acid system when electrolyte temperature is 24 ℃,electrode space is 70 mm and current density is 100 A/m2.The method has simple process and flexible operation,is environment-friendly and has great industrial application potentials.