A sealing device includes an annular reinforcing ring and an elastic body part, and the elastic body part has an annular seal lip, an annular dust lip, and an annular side lip. The side lip extends toward the outer side on an outer periphery side of the dust lip, and includes a distal end portion, a middle portion, and a root portion. The root portion is an annular portion, the middle portion is a portion that is outside of the root portion, and an annular portion that increases in diameter toward an outward side, and the distal end portion is a portion that is outside the middle portion, and an annular portion that increases in diameter toward an outward side. The distal end portion is bent to an inner periphery side from the middle portion.