Abstract: According to the ore property in a gold cyanidation plant, experimental study on the replacement of sodium cyanide by environment-friendly gold leaching agent was carried out, as well as its application. The results show that under the same process flow of all-sliming cyanidation CIP, the environment-friendly gold leaching agent can totally replace sodium cyanide in production, with the gold leaching rate reaching 97.58%, which is equal to that of sodium cyanide and lower in cost. The environment-friendly gold leaching agent has significant economic and environmental benefits.