This study focuses on the characterization of a secondary copper slag (ECS) generated by a company located in the Valle del Cauca region, Colombia, for possible use as an addition to the cement production process. A particle size distribution (DTP), chemical characterization (FRX), mineralogical characterization (DRX) analysis is performed, and finally, the pozzolanic activity of fine secondary copper slag (ECF) is evaluated using the method set out in ASTM C 311 using the Resistance Activity Index (IAR). ECF was found to meet the chemical conditions to be classified as pozzolanic and resistance conditions according to ASTM C618 and ASTM C311 standards respectively, with an IAR of 67.37 % to 7 days and 78.56 % to 28 days. It was also found that the main mineralogical components of are leucite and pyroxene, and that the vitreous phase percentage of the slag is 45.8 %, with these results making it possible to use this waste in cementing materials manufacturing processes.