The effects of surface scratch and oil starvation on elastohydrodynamic lubrication (EHL) was studied experimentally.Using the interferometry technique,oil film shapes were observed under high load and heavy load with different scratch locations.The midsection film thickness profiles were obtained by MBI software.Compared with the smooth results,it has been found that the effect of the scratch on film thickness is more obvious under light load.Compared with the full flooded results,it is seen that the fluctuation in film distribution is decreased by the scratch under oil starvation and the elastic deformation of the groove is altered.