We present the essential structures of compensating test system for high order aspherical plates and high order aspherical surfaces, of which R-C and Quasi-R-C systems with aperture of 1 meter, f/8 and FOV of 1 degree.5 are composed. All these compensating test systems reach very high compensating accuracy, the residual of most tested surfaces is less than (lambda) /100. A formula of third order spherical aberration is derived and applied to initial solution of compensator. The initial structure of the compensator is in correspondence with the optimal result very well. Finally, taking high order aspherical plate as an example, we discuss in detail the test system errors, and give some ideas of reducing test system error or loosing requirement of fabrication tolerance.