The electrical contact of pantograph-catenary system refers to the physical and chemical phenomenon that the pantograph slide plate and the catenary contact line contact each other and realize the current transmission through the contact interface. The electrical contact of pantograph-catenary system includes three phenomena and problems: static electrical contact, sliding electrical contact and separable electrical contact. In this paper, the thermal process of pantograph-catenary system under static electrical contact, sliding electrical contact and separable electrical contact is discussed respectively. The contact temperature rise-contact pressure-flow relationship between pantograph slider and rigid catenary under static state is studied experimentally. The contact resistance, contact temperature rise, contact material matching and friction and wear of pantograph-catenary system are systematically introduced. The causes and effects of arc in pantograph-catenary system are expounded in detail. The requirements of pantograph-catenary electrical contact and the evaluation of contact quality are summarized. Contact resistance is the basic parameter of pantograph-catenary electrical contact, which is related to pantograph-catenary material matching, contact pressure, contact form and contact surface condition. Different combinations of slider and contact wire materials have different contact resistances. When the electric train is stationary, the flow of the pantograph skateboard must be kept within the allowable limit. The test results show that when the contact pressure between pantograph and catenary changes in the range of 60 N ~ 120 N, the contact temperature rise-contact pressure-flow relationship between pantograph slider and rigid catenary is insensitive to the change of contact pressure, and the static electrical contact characteristics of pantograph and catenary system cannot be significantly changed simply by increasing or decreasing contact pressure. The factors that determine the static contact pressure of pantograph-catenary system include the static air intake of electric train, the arcing rate of pantograph-catenary system and the material matching between contact line and pantograph slide plate. The simulation results of thermal process of contact wire caused by pantograph-catenary system current show that normal starting current will not affect the operation reliability of pantograph-catenary system, and the damage of short-circuit current to contact wire of pantograph-catenary contact point is often fatal. There are three kinds of wear during the sliding contact between the slider and the contact line: mechanical wear, chemical wear and electrical wear. Mechanical wear is usually divided into adhesive wear, hard particle wear and fatigue wear. In most cases, when the slider is out of contact with the contact wire, the disconnection current is greater than the arcing current, and the voltage between the slider and the contact wire is greater than the arcing voltage, so the arcing phenomenon of pantograph-catenary system is inevitable. Power shortage? Only? Where is it? What? It is very important to ensure the continuity of current collection of EMU for the transmission of moving contact energy. There are many reasons for the phenomenon of electric spark and arc in pantograph-catenary system, and the influence of arc on pantograph-catenary system materials is different under different conditions. Based on the heat conduction theory, the arc ablation model of pantograph-catenary system is established, and the calculation of the thermal process of the contact line being ablated by arc is reduced to solving the strong transient heat conduction problem of a semi-infinite object with constant heat flow and rapid heating with the second boundary condition. The simulation results of thermal process of contact wire under the conditions of static arc and dynamic arc show that the static arc and dynamic arc have different corrosion degrees on contact wire. Static arc can melt the contact line surface in a very short time, and the erosion degree of moving arc at different speeds is different. The higher the running speed of the electric train, the smaller the erosion degree of the arc on the contact line surface. The contact quality of pantograph-catenary system is often indirectly evaluated by measuring the dynamic contact pressure, arcing rate and contact line elevation at the positioning point, and the running life of pantograph-catenary system is evaluated by the wear of sliding plate and contact line.