Abstract: It is important for the design of radio communication system to understand the plasma distribution in high-temperature flowfield. A numerical method to simulate the complicated plasma flow field around a hypersonic flight vehicle is developed by solving the Navier-Stokes equations with thermo-chemical nonequilibrium source terms. The method is validated by comparison of the distribution of electron number densities with flight experiment. The effects of chemical reaction and thermo-chemical nonequilibrium models, the wall temperatures and catalytic activities on the computational results are studied. The distribution of plasma in flow over a lifting body are investigated too. The results show that the electron number densities computed by sevenspecies and elevenspecies chemical model are different obviously when the flowfield temperatures beyond 10000K, and in the case O+ must be taken into account in chemical reaction models besides NO+. The wall conditions, especially the catalytic activities, have a more important effect on the distribution of plasma, the reliable data of the wall catalytic activities, have a more important effect on the distribution of plasma, the reliable data the wall catalytic activities, have a more important effect on the distribution of plasma, the reliable data of the wall catalytic activities, have a more important on the distribution of plasma, the reliable data of the wall catalytic activities and temperatures must be obtained firstly in order to simulate exactly the plasma flow over a lift body.