Stribeck curves and the maximum oil film thickness formula of HamrockDowson were used to analyze the relationship between the friction force and the speed and oil supply of rolling linear guide.The results show that,under certain conditions,with the increasing of speed,the lubrication of rolling linear guide will experience three phases:boundary lubrication,mixed lubrication and elastohydrodynamic lubrication,and the friction force is decreased first and then increased.With more supply of lubricating oil,the linear guides will work in a good lubrication state,and the friction force will decrease.The experiments were carried out on the test bench for comprehensive performance of rolling linear guide to study the influence of speed and oil supply on the friction force of rolling linear guide.It is found that speed has a great impact on friction force under the highspeed operation.With the continuous increases of oil supply,the friction force is decreased quickly first and then the friction force curve becomes flat.The oil supply amount at the flat beginning stage of friction force curve is the optimal lubrication quantity.