Abstract: The quasi static analysis of radial cylindrical roller bearing is introduced.The influences of the out of round raceway,the relative inclination of the roller and race,and flexible deformation of the bearing housing on bearing performance are taken into consideration.The calculation of out of round raceway and the counter rotating intershaft support bearing characteristics are studied.The precise determination of roller loading in an inclined inner race is presented,and the calculation of contact force on the inclined roller is carried out by means of the transverse“slicing”technique.The maximum stress of roller are calculated with the flexible two dimensional contact variational method.The thermal effects of oil in Hertzian zone and the entry region and the oil starvation influence are also taken into account in the lubrication model.The main bearing in an aeroengine was calculated with the quasi static analysis program on the M 150H computer.The agreement of calculated and experimental results is quite good.