To provide the combining structure of a cylinder liner with a piston ring which are used for an internal combustion engine for a ship, an automobile, and the like, and also for the others, and excellent in abrasion resistance and seizure resistance.

A piston ring and a cylinder liner which are used for an internal combustion engine, comprise a piston ring having a coated layer in which at least one kind of a hard ceramics coating or a compound chrome plating is applied to the peripheral surface thereof, and a cylinder liner formed of copper consisting in a manner that it includes C: 0.25-2.2%, 0.6 to 18wt.% in total of at least more than one kind of Cr, Mo, W or V, the residual Fe, and an obligatory impurity. Then, the inner circumferential surface of the cylinder liner is nitrided, thereby a nitrided layer can be arranged, in which the hardness (Hv) of a layer from its surface to more than 30μm in depth is 400 or more, and the porous layer of the upper most surface of the nitrided layer can be set less than 5μm by honing working after nitriding.