In order to improve the results of high speed wind tunnel test of rotor airfoil in engineering, the existing single parameter linear wall pressure method is simplified and applied to the data correction. The simplified method is used to correct the OA309 rotor airfoil test data in FL-21 wind tunnel. Comparison results show that the modified aerodynamics performance curves of rotor airfoil are in good agreement with the abroad data. The method can effectively meet the requirement of data correction of high speed wind tunnel test of rotor airfoil.