In a rolling bearing with seal, an annular lip supporting portion having a larger thickness than that of a seal lip is formed on an inner periphery side of a seal member; the seal lip protruding on an inner peripheral surface of the lip supporting portion has: a cylindrical seal surface being in close contact with an outer peripheral surface of an inner race; and an inner side surface at least part of which in a region from an inner end of the seal surface to reach the lip supporting portion stands upright from the inner end of the seal surface in a direction perpendicular to a generating line of the outer peripheral surface of the inner race; and a width of the seal surface in an axial direction is set to be larger than a height of the seal lip in a radial direction. Accordingly, it is possible to provide a rolling bearing with seal with a simple structure, which is capable of maintaining a normal seal pressure against an inner race of a seal lip even when large negative pressure or positive pressure acts on the seal lip, thus preventing leakage of grease inside the bearing.