Highspeed grinding tests were conducted on a special test rig under wet and dry conditions,and the effects of water presence on the grinding stone force,rail cutting volume,grinding stone wear rate,and rail surface roughness were studied.The results show that the grinding stone lateral force fluctuation under wet condition is smaller than that under dry condition,which is preferred for the highspeed grinding operation.The rail cutting volume is decreased a little under wet condition,which has slight influence on grinding operation.The grinding stone wear rate is reduced and rail surface roughness after grinding is improved under wet condition,which is beneficial to the highspeed grinding.