With the acceleration of urbanization and the continuous growth of power load, cable, as an important part of the distribution network, plays a key role in the urban transmission and distribution system. However, long-term load operation or excessive fault current will cause the cable temperature to rise, accelerate the aging of XLPE material, and even cause fire. Cable arc phenomenon is characterized by high temperature and high energy density, so it is important to study its temperature field and energy field for cable fire prevention and control. In this paper, based on COMSOL software, the simulation model of cable arc is established by using magnetic fluid dynamics (MHD) model, and the temperature distribution and energy transmission characteristics of the arc under different current and aperture conditions are analyzed. The results show that the increase of current density will lead to the increase of arc column temperature, and the change of aperture will affect the heat conduction and heat dissipation capacity of arc. This study can provide a theoretical basis for cable fire prevention and protection measures.