Abstract: Ground-based testing represents a critical method for plasma flow field characterization. To address the requirements for plasma parameter identification in high-enthalpy flows, this study performed experimental measurements of typical plasma parameters in an arc-heated wind tunnel. A blunt wedge flat-plate model with angle of attack was used to simulate spacecraft flow fields over large surface areas. The spatial distribution of electron density in the wedge model flow field was measured using electrostatic probe diagnostics combined with motorized scanning technology, while corresponding numerical simulations were conducted for comparison and validation. The investigation revealed that under current wind tunnel conditions, plasma parameters remained essentially uniform and stable within the 80 mm thick core region along the z-direction of the rectangular nozzle. However, electron density showed significant attenuation near the nozzle sidewalls due to boundary layer effects. The employed probe measurement scheme demonstrated minimal influence on electron density detection. For relatively high electron density conditions (～10¹¹ cm^–3), measured values agreed well with simulations, showing deviations less than 0.5 orders of magnitude. In contrast, under low electron density conditions (～10¹⁰ cm^–3), measured values significantly exceeded computational results by 0.5–1 orders of magnitude. Preliminary analysis indicated that copper contamination from electrode ablation served as a major contributing factor for this discrepancy. This study provides an effective validation method for near-wall plasma parameter measurements in aircraft applications.