Abstract: The statement debugging is important but time-consuming work in the arc-heated turbulent flat plate testing. Specially, with the development of the alerting angle method in recent years, the debugging becomes more complex and further consuming in both time and cost. In order to guide the experiments, some CFD analyses of the flow characteristics under different testing conditions are completed with the FLUENT software. By comparing to the experimental measurements of a calibration-plate under some representative conditions, the numerical method is verified firstly. At the same time, the distributions of the primary aerothermal parameters over the plate surface are provided quantitatively under various attack angles and total pressures. Furthermore, by analyzing the shock wave reflection, interaction and boundary layer separation, the rules of the impact of the control parameters to the flow field and some basic principles in experiments are summarized.