In order to test concave aspheric surfaces precisely, a multifunctional computer-generated hologram (CGH) which can compensate wavefront in null test, adjust the relative position between CGH and interferometer and adjust the relative position between CGH and the tested aspheric surface is proposed and designed. It consists of three segments, called main CGH, alignment CGH and fiducial CGH. The principle of testing aspheric surfaces is reviewed and the design method is introduced. The pros and cons of the auxiliary CGH adjustment method and the common adjustment method are compared. Then a design example for testing a paraboloidal mirror (Φ187.72 mm、F number is 1.71) is presented. The effects of CGH fabrication errors on the accuracy of interferometric measurements are analyzed. The accuracy of using a CGH to measure the surface is 4.47 nm. The designed CGH meets the requirements of high precision aspheric surfaces testing.