One of the auccessfull applications of computer holography is the testing of aspherie surfaces.Computer generated holograms (CGH s) provide an ideal reference wavefront for the test. Thig paper describes briefly the principle and experiment of the testing of aspherics with compensating method using computer-generated interferograms (CGI), and proposes a testing system that does not introduce additional aberration. We used the CGI as a compensating plate and inspected the surface according to Moire fringes. The relation between the aspheric surface figure and the intensiisy distribution of Moire fringes is analysed and simulated on a computer. Various factors that could possibly affect the test precision are discussed. The set-up used is very simple and convenient to adjust.