Abstract: A rotary shaft end seal for apparatus operating under pressure comprises a set of working members which are located between the end faces of annular shoulders provided on the shaft and on the housing encompassing the shaft. The set of working members is accommodated in a chamber providing for circulation of sealing fluid. The set of working members consists of an antifriction sliding ring and an elastic ring, each being in contact with the end face of one of said annular shoulders, as well as of a metal ring disposed between the antifriction ring and the elastic ring, said metal ring being loosely mounted on the shaft. The annular shoulders of the shaft and housing are arranged in such a manner that the force from the internal pressure in the apparatus tends to cause an axial displacement of the shaft so as to compress the set of the working members, and the shaft is spring-loaded so as to be biased in the direction of said displacement.