Friction and wear are very important in mechanical design. This paper studies the friction and wear characteristics of 45 steel under oil lubrication. The sliding friction and wear experiment was carried out with the pin plate friction pairs on the MMW-1A friction and wear test machine. Researching the influence of velocity on friction factor under the same load, the relation between wear and load and wear analysis under the same speed different loads. The results showed that under the same load and with the increase of velocity, the friction factor had a gradually decreasing trend. When some of the parameters were certain, the wear volume and the loading force was roughly linear relation. Pitting occurred when the load increased.