In view of the characteristics of experiment equipment for automotive aerodynamic force and the requirement of data processing and its result, a certain mathematic model was built. Also, software of automotive wind tunnel data processing was developed, by virtue of Visual Basic 6.0. The data was extracted, analyzed and displayed by reading data files in format TXT. The software integrated Excel software successfully. Users could observe and analyze the aerodynamic force and coefficient of automotive wind tunnel model intuitively. The paper discussed software structure, data processing method and display technology of the software. Finally, the software has already been used in the HD-2 wind tunnel test of Hunan University.