An antifriction bearing in an annular gap between respective coaxial faces of a rotating body and a stationary body is sealed in an axial direction against loss of lubricant and contamination by foreign matter by means of a seal mainly constitutued by two sealing rings. The first ring, fastened to the rotating body has a frustoconical face portion obliquely directed toward the axis, a second substantially cylindrical face portion axially coextensive with the first face portion and of smaller diameter than the smaller base of the first face portion. It is directed radially outward and is connected with the smaller base of the first face portion by a third, substantially radial face portion. The second sealing ring has a frustoconical face closely adjacent the first face portion and bounds therewith a narrow passage extending obliquely from an inner orifice near the aforementioned smaller base to an outer orifice adjacent the larger base of the first face portion. The two sealing rings are fastened to the two bodies so that they rotate relative to each other during operation of the bearing.