Abstract: Hypervelocity impact generated plasma (HVIGP) was investigated through both theoretical analysis and numerical simulation. The 2-D axially symmetric model was established based on the smoothed particle hydrodynamic method, to numerically simulate the impacts of different velocities and verified by comparing to the debris clouds and expansion velocity. The SPH particle temperatures at different hypervelocity were calculated by the Thomas-Fermi model and considering the plasma parameters as the vaporized parts. In addition, the relationships between the electron density of the thermal non-equilibrium plasma, the electron temperature, the macro-temperature, and the internal energy were given based on statistical physics and chemical reaction dynamics to calculate the parameters of HVIGP. Total charges of HVIGP at different times were simulated. The simulated results are compared with the calculated results by the empirical formula, indicating that the method used to calculate HVIGP in this paper is correct.