A possibility of iron and part of sulfur removal from chalcopyrite, contained in sulfide copper ores through removal of iron sulfides, formed as a result of chalcopyrite breakdown by sulfur-containing products, has been considered. Elemental sulfur and reduced gases of pyrometallurgical processes, containing sulfurous anhydride, were tested as sulfur-containing products. Based on the obtained data, a flow sheet is proposed, reducing sulfur emissions in processing of sulfide copper ores, containing chalcopyrite.