The present invention proposes a double sealing device for a rotating shaft and a pump including such a device. Device comprising a first and a second seal mounted side by side in a circular cylindrical housing through which the shaft to be sealed passes, each of these seals being composed of, on the one hand, a carrier ring of metal material with an outer axial flange and an inner radial flange and, on the other hand, a sealing washer forming a sealing lip bearing slidably on the shaft, the first seal keeping a first fluid medium sealed off and the second seal keeping a second fluid medium sealed off. Double sealing device (1) characterized in that the axial flange (8', 9') of at least one of the carrier rings (8, 9) of the first and second seals (3, 4) has an extension at its free end forming a pierced or cut-out ring structure, not covered by the sealing washer of the corresponding seal (3, 4), and located substantially facing the peripheral groove (7) and pointing towards the other seal (4, 3).