© 2015, American Institute of Aeronautics and Astronautics Inc, AIAA.Five-hole pressure probes are used to measure total and static pressure, magnitude and angles of flow velocity vector. Calibration procedure is of high importance to obtain ac- curate results. Different approaches are proposed in literature to obtain calibration coefficients and data reduction algorithm. In this paper, a significance analysis is conducted for the parameters of the third-order multiple regression model used in data reduction process. A new multi regression curve fitting is applied with the most significant parameters. The new reduced model gives more accurate results compared to the first-order regression whereas extensive data acquisition process of the third-order model is eliminated with reduced parameters.