Abstract: The breakdown of high-voltage cable porcelain bushing terminal leads to the porcelain bushing burst accident, which greatly affects the safety of electric equipment and personnel. In order to study the mechanism of porcelain bushing burst caused by faults, a simulation model is established by taking the Japanese-style high-voltage cable porcelain bushing terminal which is widely used in the market as an example, the mechanism of the transient heat and the effect of high temperature and high pressure plasma on the burst of the porcelain sleeve of high voltage cable caused by the failure of the porcelain sleeve terminal is analyzed, and the reason of porcelain bushing burst is found. In the end, some measures to reduce the secondary damage caused by the end failure are put forward.