The algorithm developed in this article is mainly used in video tracking of two-axis turntable.The methods using angle deviation between target and the video center to correct the azimuth and pitching angle error directly can achieve good performance only when the pitching angle is close to zero.Large pitching angle will result in big error.To resolve the problem,a mathematic model based on coordinate transform was made,and the new algorithm based on the model can be used in any situation with high precision,and the inputs and outputs of the algorithm is definite.