A sliding member includes a superficial portion forming a sliding surface. The superficial portion includes an oxygen-containing alloy containing at least one metallic element selected from the group consisting of molybdenum and tungsten in an amount of from 2 to 80% by weight; and oxygen in an amount of from 0.5 to 15% by weight. The sliding member sustains lubricating characteristics given to the sliding surface over a long period of time to maintain a low friction coefficient and durability.