In this paper, based on MHD theory, the coupling of high speed air flow and arc produced by 110kV transmission and distribution network gas blowing arc extinguishing device is studied by using Comsol Mutiphysic simulation platform. It is found that the time point control of the device gas blowing initial arc extinguishing is in the early stage of arc transient development, that is, the time range from the lightning pulse peak to the first power frequency period is the best time to extinguish the arc, during which the arc has a low conductivity state. The arc column has the characteristics of small radius and weak energy, so the arc blowing can ensure that the arc can be completely extinguished and insulated.