Abstract: 3 mm-thick Cu-Al cold-rolled composite plates were annealed at different temperatures for different time.The effect of annealing treatment on the microstructure and mechanical properties of the plate was studied by scanning electron microscope, optical microscope, tensile testing machine, XRD diffractometer and hardness tester. The results show that with the increase of annealing temperature and annealing time, the matrix layers at both sides undergo differential recovery and recrystallization, the microhardness of the matrix layers decreases, and the overall tensile performance increases.Three intermetallic compounds of Al₂Cu, Al₄Cu₉ and AlCu are formed at the interface, which increases the microhardness at the interface. Too high annealing temperature and too long annealing time make the combined interface diffusion layer too thick, and a large number of brittle intermetal compounds lead to the delamination fracture of the composite plate during stretching.