In order to improve the interpolation accuracy, the five-hole probe aerodynamic data interpolation method is discussed and a three-dimensional linear interpolation method based on traditional linear interpolation method is developed. The calibration graph of the same probe under different Mach numbers is formed into a three-dimensional database in this method, and the experimental data are interpolated through one three-dimensional graph. The two interpolation methods before and after the improvement are used to deal with the experimental data of a calibration wind tunnel respectively. The comparison results show that the three-dimensional linear interpolation method is superior to the traditional one on the interpolation precision under the condition of continuous changes in the experimental condition, especially when the incoming Mach number changes sharply. This method can improve the data accuracy compared with that using a single calibration file, and can be used in automatic flow field measurement system featured with high-speed and high-precision data acquisition.