In order to elucidate the mechanism and factors of tooth face pitting, roller tests were carried out. In the tests, the oxidized-nonmartensitic layer, surface roughness, case hardness and residual compressive stress were noted as material factors, and sliding, oil temperature and viscosity were as running condition factors. As a results, the pitting could be classified into two forms according to crake origin; subsurface origin pittinng and surface origin pittinng. In the case of subsurface origin pitting, the pitting life coincides with the value estimated from shear stress and shear strength relating to Vickers hardness. In the case of surface origin pitting, the influence of shot peening could be regarded as a pile of influences of surface roughness, hardness and residual compressive stress. These factors of shot peening, the existence of the oxidized-nonmartensitic layer and specific sliding determined the life of surface origin pitting. The life of tooth face pitting could be calculated using these results of the roller tests.