In the present investigation, using a rolling contact fatigue testing machine, the surface durability (pitting limit) of steel rollers which are case-carburized and hardened to 750 Hv is examined under rolling/sliding conditions. Four kinds of rollers which are finished to a surface roughness of about O.2μm Rmax or about 3μm Rmax by a cylindrical grinding machine are used. To improve the ground surface the shot peening and barrelling processes are employed and they are compared to the non-treated surface. The processes of shot peening and barrelling can be applied to surfaces with complex configurations, such as gears. It is shown that the surface durability of rollers whose surfaces are subjected to a barrelling process after a shot-peening process is improved.