A rolling bearing comprising an outer race having one track, an inner race having the other track, a plurality of rolling elements arranged between the both tracks, and a cage for retaining the plurality of rolling elements in such a way that the rolling elements can roll freely, wherein the cage is a lubricating oil-containing polymer member obtained by molding a synthetic resin containing 10 to 80% by weight of a lubricating oil. The cage retains a sufficient amount of a lubricating oil at a high rate of retention so that a lubricating action can be maintained in a stable manner for a prolonged period of time, and it is produced at low cost.