The rolling-contact bearing comprises a rotating race and a non-rotating race through each of which there pass ducts (6, 7) for passage of fluid, rolling elements (3) between the rotating and non-rotating races, and a sealing device (8) fitted between the rotating and non-rotating races in order to form a leaktight intermediate chamber (14) communicating with the ducts (6, 7) for the passage of fluid. The intermediate chamber has two flexible walls (11) of which the free end parts form two sealing lips (12) in frictional contact with a contact surface (13) of one of the races (2) of the bearing. The frictional contact surfaces (13) are inclined with respect to the axis (XX') of rotation of the bearing. The flexible walls (11) extend substantially parallel to the contact surfaces so that the contact pressure between the sealing lips and the surfaces varies in the same direction as the pressure of the fluid in the intermediate chamber (14) of the sealing device.