A sealing device that suppresses degradation of sealing properties resulting from conduction of heat generated by sliding of a resin-made sealing member and a rotating shaft to a rubber-made sealing member. The sealing device includes a rubber sealing member (110), a resin sealing member (120), a support ring (130), and a case (180), the support ring (130) has: a large diameter portion (131); an inward flange (135) that extends inwardly in a radial direction from an end portion of the large diameter portion (131) on an air side, and has a notch (135a) with which a nail portion (183) of the case is engaged; a small diameter portion (133) that is in contact with an inner peripheral surface of a lip portion (112) of the rubber sealing member (110); and a lip retaining portion (134).