Effects of annealing time and temperature on microstructure and properties of cold-rolled Cu-Mg-Te-Y alloy have been studied. The results indicate that after cold rolling, the microstructure presents a fiber texture, the internal grain orientation changes and Vickers hardness increases while electrical conductivity decreases. After annealing treatment, Vickers hardness decreases with electrical conductivity and elongation improved. With the annealing time prolonging, the magnesium as solution atom in copper alloy escapes from copper lattice and segregates around Cu2Te phases through diffusion paths such as dislocations, so electrical conductivity goes up. In turn, electrical conductivity goes down when the grain boundaries become continuously more owing to the recrystallized new grains. Consequently, the optimum overall performance of Cu-Mg-Te-Y alloy is gained under a certain annealing process including annealing temperature of 360~390 oC and annealing time within 1 h.