Conventionally, copper ores are treated and processed by a high-energy intensive pyrometallurgical process. However, the huge amounts of emission of obnoxious gases demand the development of a simple, low-cost, and environmentally friendly technique. In this work, the dissolution kinetics of goldfieldite ore in ammonia-ammonium chloride was investigated. The influence of some experimental conditions were critically developed. It was affirmed that the dissolution rate increased with increasing concentration, reaction temperature, and decreasing particle diameter. At optimized experimental conditions (0.5 mol L-1 NH3-NH4Cl, 75°C, 45 μm), 88.2 copper dissolution was recorded with calculated activation energy, Ea, of 19.4 kJ mol-1. © 2023, University of Chemical Technology and Metallurgy. All Rights Reserved.