In order to design optics-eletricity system for high speed vehicle, the mirror is replaced by fast steering mirror, and stabilization platform of complex axes is designed for optics-eletricity system with upside mirror. Through theory analysis, vector equation of line of sight for the platform was calculated, movement characteristic and compensation theory of stabilization for complex axes was analyzed, and controlling method of complex platform was presented. In the end, influence of assembly axes error to system error was studied for engineering application. The research result indicate that , Stabilization platform of complex axes for optics-eletricity system with upside mirror implement compensation to error of first platform, bandwidth of system is 200 Hz, which is approximately equal to bandwith of fast steering mirror, and stabilization precision of system is upgraded, but assembly error of second platform should less than 0.05 mrad.