Copper selenides are attractive materials for high-temperature thermoelectric applications. They exhibit remarkably enhanced thermoelectric properties originating from their superionic liquid character. In this work, the synthesis of Cu-Se compounds is investigated using mechanical alloying, aiming to obtain the Cu2Se phase and modify the crystal structure by annealing at high temperatures and quenching. In the first part, Cu-Se powders are prepared at various milling times. They are characterized regarding their structure, morphology and composition by X-ray diffraction analysisand scanning electron microscopy. After 2.5 h of synthesis,α-Cu2Se andβ-Cu2Se was attained in the powder, with the former having the highest percentage contribution. The crystallite size of these phases was calculated to be in the range of 17.0-19.6nm. The synthesized powder consisted of grains with dimensions from nanometers to micrometers and their aggregates. A trace of a possibly surficial layer of copper oxide was also detected on the sample. In the second part of this study, the optimum synthesized powder wassubjected to 2 hof annealing at 650 °C, followed by quenching. According to X-ray diffraction analysis,the percentage contribution of the thermoelectrically inferiorα-Cu2Se phase increased being the vast majority of the material and almost eliminated β-Cu2Se. The crystallite size was calculated to be in the range of 31.2-34.5nm. Overall, the desired Cu2Se compound can be obtained by the mechanical alloying technique asα- and β-phase, and the crystal structure can be modified by annealing under appropriate conditions.