The cryogenic laser peening (CLP) of 2024-T351 aluminum alloys is performed. The results show that the effective grain refinement on the surface of 2024-T351 aluminum alloys is induced by the CLP, the grain size in the severe plastic deformation layer is mostly smaller than 10 μm, and the second-phase distribution is more homogeneous. Compared with those of untreated samples, the surface hardness, the tensile strength and the yield strength of samples treated by the CLP increase by 34.1%, 21.6% and 28.9%, respectively, and the elongation of materials increases slightly. The simultaneous improvement of strength and ductility is realized. The tensile fracture morphology indicates that the fracture form of 2024-T351 aluminum alloys strengthened by the CLP is a ductile fracture which is beneficial to improve the tensile property of aluminum alloys.