A spherical plain bearing comprising an inner ring provided with a spherical outer surface and with lateral surfaces, an outer ring provided with a corresponding spherical inner surface mounted on the outer surface, and a sleeve mounted into a bore of the inner ring. The inner ring comprises at least three part rings which are mounted in contact in the circumferential direction one relative to another. At least one protrusion is provided on an outer surface of the sleeve and extends into a groove formed on the bore of the inner ring. The sleeve leaves the lateral surfaces free of the inner ring.