Abstract: The principles of aerostat radar servo system are introduced. Based on the method of strap-down stabilization,the realization of the function of servo system which is given in the airspace stabilization algorithm is proposed . The system robust control method in the loop control of the primary principle is expounded emphatically, and the speed loop robust controller of the designing process is described. Compared with the traditional control mode, the simulation result indicates that the robust controller has better adaptability in airspace stabilizing function.