The Cu-Li-Mg system still remains very unknown. Mel'nik et al. (Russ. Metall. 3 (1976) 152-156) studied it at 643 K. They considered the existence of a stoichiometric compound Cu8Li2Mg15 with an orthorhombic structure. In this work, the Cu-Li-Mg system was studied at room temperature by means of SEM (scanning electron microscopy) / EDS (energy dispersive spectroscopy) and X-ray diffraction. Results were compared with the ones from (Russ. Metall. 3 (1976) 152-156) and with the assessments for the binaries Cu-Li, Cu-Mg and Li-Mg present in the literature (COST-507, Thermochemical database for light metal alloys, in: I. Ansara (Ed.), Concerted Action on Materials Sciences, European Commission DGXII Publ., 1994, pp. 132-134; A.A. Nayeb-Hashemi, J.B. Clark, Phase Diagrams of Binary Magnesium Alloys, ASM International, 1988, pp. 184-194).