The electrical conductivity of carbon black is closely related to the changes in the internal microstructure, surface properties, particle size and structure of carbon black particles. The change of the internal microstructure of carbon black particles has a significant effect on its electrical conductivity, and the graphitized carbon black has higher electrical conductivity. When the surface of carbon black contains volatile or tar-like impurities, that is, solvent extracts, the surface of carbon black is covered with a film of oxygen-containing compounds, and an insulating layer is formed on the surface of carbon black particles. The existence of this insulating layer will significantly increase the resistance of carbon black. When carbon black is heated in vacuum or inert gas to remove oxygen-containing volatiles and oily impurities, its resistance will be significantly reduced. When the particle size of carbon black decreases, that is, when its dispersion increases, the resistance decreases due to the increase in the number of particles per unit volume. Therefore, it can be said that carbon black with finer particles has better conductivity, and the structure of carbon black is an important factor affecting the conductivity of carbon black, which is obviously due to the existence of carbon black chain branch structure or fiber structure.