Aiming at the problems of complex and inaccurate calculation of traditional attitude angle calculation procession, the vector angle coordinate system is established according to the theory and engineering practice method, and the transformation and angle definition relationship between different flight attitude coordinate systems is given, which can accurately calculate the poseangle size of the corresponding coordinate system and determine its direction, especially in the channel coupling calculation, so that the attitude angle calculation between the coordinate systems is only related to the angle, but not to the order of the coordinate system change diange. The results show that this proposed method simplifies the calculation process and solve the problem of complex and large error in attitude angle solving during in wind tunnel test and aircraft motion.