Abstract: Ground-based testing serves as a crucial approach for characterizing the properties of plasma flow fields. In response to the need for plasma parameter identification in high-enthalpy flows, this study conducted experimental investigations of typical plasma parameters in an arc-heated wind tunnel. A blunt wedge flat-plate model with an angle of attack was employed to simulate the flow over large-area regions of a spacecraft. Spatial distributions of electron density in the model's flow field were measured using electrostatic probe diagnostics in conjunction with an electrically actuated scanning mechanism. In parallel, numerical simulations were performed under equivalent conditions, and the experimental and computational results were compared for validation. The results indicate that, under the current wind tunnel conditions, the plasma parameters within the 80 mm thick core region along the Z-direction of the rectangular nozzle remain generally uniform and stable. However, near the nozzle walls, the electron density shows significant attenuation due to boundary layer effects. The probe measurement scheme adopted in this study exerts minimal influence on electron density measurements. For conditions with relatively high electron density (～10¹¹ cm^–3), the experimental values closely match the simulation results, with deviations less than 0.5 orders of magnitude. In contrast, under low electron density conditions (～10¹⁰ cm^–3), the measured electron densities are substantially higher than the simulated values, with deviations between 0.5 and 1 order of magnitude. Preliminary analysis suggests that copper contamination resulting from electrode ablation is a significant contributing factor.