The surface of the copper sample was sprayed with a soot solution, and the electrical contact fretting test of copper under different loads was carried out in the selfdeveloped experimental equipment.The wear marks were analyzed by 3D shape spectroscopy and SEM.The results show that the load has a significant effect on the electrical contact properties of the material.Contact resistance is inversely proportional to normal load, that is, increasing the load can improve the electrical contact performance of the friction pair.The effective conductive area is limited in the contact area, so that the contact resistance no longer decreases as the load increases when the load reaches a certain value.Under small loads, the addition of soot deteriorates the electrical contact performance of the friction pair.As the load increases, this deterioration gradually decreases.The friction coefficient is decreased with the increase of the load.When the load is low (from 2 N to 6 N), the friction coefficient curve shows obvious rising period, running period, falling period and stable period.However, there is only rising period and stable period when the load is high (from 8 N to 10 N).Under large load, the contact area is well matched, and the friction pair surface quickly reaches the equilibrium point, so the friction coefficient is relatively stable.Under the action of electrochemistry, the soot particles form a solid film on the surface of the friction pair, which acts to reduce friction and wear.