For the hydraulic cylinder system of construction equipment to function normally, the hydraulic oil should not leak under high pressure, and the leakage begins with various seals of damage. The frictional heat caused by the reciprocating motion inside the cylinder increases the temperature of the oil, which affects the aging of the seal materials inside the cylinder, thereby accelerating seal damage. The purpose of this study is to confirm the effect of reducing heat generation by applying umbrellatype micro-dimples on the surface of a wear ring, and to find out the performance according to changes in shape and density of the dimples. Dimples were manufactured by injection molding and the core for injection was made by profile grinding processing. The structural safety of the wearing with dimples was examined by structural analysis, and the temperature changes of the dimple were measured during pin-on-disc friction experiments. It was confirmed that the dimple was effective in reducing the amount of heat generated, and the heat generation decreased as the size and density of the dimple increased.