Abstract: A positive retaining ring system for axially securing a work element to a shaft which consists of a shaft provided with an annular recess having a trapezoidal cross-sectional configuration and which extends partially below a work element positioned on the shaft against a work element retaining shouler provided thereon. A segmented annular retaining ring having substantially the same trapezoidal cross-sectional configuration mounted in the recess with the vertical side thereof abutting the side of the work element. Clamping means circumferentially mounted on the segmented ring so as to exert an axial force thereagainst to wedge the ring into the annular recess. The resultant wedging force is translated into an axial force against the side of the work element so as to positively lock the work element against the work element retaining shoulder provided on the shaft.