The theoretical model of fluid lubricant of a flatonflat contact was established under condition of quantitative oil supply.The characteristics of film thicknessvelocity of surface contact pair and the effect of various operating parameters on contact zone lubrication were numerical analyzed.The results show that under quantitative oil supply,the phenomenon of starved oil appears in a certain entrainment speed,and it is gradually deteriorated along with the increase of entrainment speed.With the increase of entrainment speed,the exit film thickness is first increased and then gradually reaches the steady value that is close to the supply oil film thickness.The numerical analysis results are in qualitative agreement with the experimental results.The less the quantity of oil supply is,or the greater the oil viscosity is,the smaller the exit film thickness changes with the increase of entrainment speed.