This research investigated the feasibility of a two-stage acidic leaching process for the treatment of copper-gold concentrates. In the first stage, copper is leached in concentrated ferric chloride solutions, while in the second stage, gold is leached in the presence of thiocyanate (SCN). The study used a copper-gold concentrate containing 45.3% copper, 20.7 ppm gold, and 259 ppm silver from a mine with saline water containing up to 4 M chloride. For the first stage of leaching, reactor leaching tests were carried out to investigate the effect of solid content, temperature, and chloride concentration on the copper extraction. The leach residues from this stage were then subjected to the second stage of leaching, where the effect of thiocyanate concentration on copper, gold, and silver extractions was studied. The experimental results show that in the first stage, nearly complete copper dissolution was achieved in the presence of 3 M chloride at 85 °C within 6 h, with over 90% of sulfide sulfur oxidized to elemental sulfur. Iron was dissolved and no iron precipitation was observed during the first stage of leaching. Approximately 97% of silver was dissolved in this stage. In contrast, gold dissolution was limited due to the high potential required for gold dissolution in chloride media. In the second stage, 88.5% of gold was leached within 1 h in the presence of 0.05 M thiocyanate at 85 °C. Compared with cyanidation, this process eliminates the need for neutralization and the side reaction between elemental sulfur and cyanide, thus reducing reagent costs.