A device serves the purpose of sealing a rotating shaft for use under water. It exhibits face seals which seal a work area against the water. In accordance with the invention the face seals are constructed in the form of three slide ring pairs, wherein between the three slide ring pairs two areas (18, 21) are arranged. One of the areas is a sealing area adjacent to the water filled with a first medium and the other area is a leaking area adjacent to the work area. In the sealing area the first medium is held at a pressure level which is higher than the pressure of the adjacent water.