This paper analyzes the error location of the ground electro optical tracking system theoretically,and determines that the main error factors affecting the target location accuracy are verticality error,zero position error,base installation error,etc.,and the calibration process of the electro optical tracking system is given. Using the sequential characteristics of coordinate transformation in the calibration process,the transformation matrix of coordinate transformation is given through the principle of singular value decomposition,including translation matrix,rotation matrix and Euler angle； at the same time,the fixed pitch offset is determined through the iteration of the calibration process. Finally,the accuracy of this calibration process was verified through experiments.