The second lip has an annular protrusion formed at one end portion in a thickness direction of a lip tip portion configured to be in sliding contact with the slinger and protruding in the thickness direction, and a thickness of the lip tip portion is formed thicker than a thickness of a lip part except for the protrusion. The protrusion is formed to be reduced in width toward the tip-side in the thickness direction and configures a sliding contact part configured to be in linearly sliding contact with the slinger. The circular plate part of the slinger is formed tilted toward the seal member in the axial direction, and the slinger has an annular flange part integrally formed therewith by bending a tip of the circular plate part so as to axially cover an area above the sliding contact part of the seal member.