Numerical analyses about sudden stop of zeroentrainment line contact elastohydrodynamic lubrication(EHL),which is common in ball screw,ball worm and roller bearing without cage,was carried out to investigate the pressure,the film thickness and the temperature of the oil film under different initial zeroentrainment surface velocities and suddenstop times.The results show that under the same sudden stop time,the central pressure and central film thickness are increased in the process of the sudden stop,and decreased slightly when initial 〖JP〗zeroentrainment surface velocity is increased.The central pressure and central film thickness are increased as the suddenstop time increases if the initial zeroentrainment surface velocity is identical.The temperature peak of the oil film is decreased slowly at first but rapidly decreased at the last stage of the sudden stop.Sudden stop of zeroentrainment causes the central pressure increase dramatically,therefore,plastic deformation happens in both two surfaces because stress surpasses the yield limit of steel,which leads to surface damage.