A cylinder liner with a plurality of protrusions on its outside surface and the manufacturing method thereof are disclosed. The protrusions are Ω-shaped, P-shaped or taper-shaped, and the Ω-shaped, P-shaped and taper-shaped protrusions are accounted for 50-99.5%, 0.5-30% and 0-20% of the total number of protrusions, respectively. The density of the protrusions on the outside surface of the cylinder liner is 15-65 per square centimeter. The outer surface of the protrusions of the cylinder liner is curved, and has a large contact area and a concave which can be filled by an aluminum sheath to improve the radial bearing capacity, so as to effectively improve the bite force between the cylinder liner and the outside aluminum sheath and prevent the cylinder liner from breaking away from the cylinder body.