Lots of wing pressure distribution data at different angles of attack and flap deflection are involved in the process of aircraft load designing, but the data from the pressure tests is generally limited. How to select an appropriate interpolation method for calculating the pressure distributing became especially important. In order to get the wing pressure distribution of an arbitrary attitude between two group angles of attack and flap deflection, which pressure distribution were constructed to two curved surface functions, and the interpolation method of curved surface coefficient was imported. According to the similarity comparing analysis between the interpolation and experiment results, it is known that the similitude coefficient between the interpolation value and experiment value is higher and has a good agreement with test data.