Retainer and bearing

The invention discloses a retainer. The retainer comprises a side ring, wherein a plurality of bridges are arranged on one side of the side ring, rolling element receiving recesses are arranged amongthe bridges, and the rolling element receiving recesses are used for receiving rolling elements so as to keep the rolling elements at intervals and guide the rolling elements. A bearing comprises an inner ring, an outer ring and the rolling elements, and a limiting piece is installed on the inner ring or the outer ring to limit movement of the retainer in the axial direction. The retainer can be inserted between the inner ring and the outer ring through an open structure on the other side of the bridges, so that the situation that the precision of the retainer is affected by deformation in theinstallation process is avoided, meanwhile, a clamping groove is formed in the inner ring of the bearing, and a clamping ring is arranged in the clamping groove for limiting the axial movement of theinstalled retainer. The hi