At present, there is a large number of aspherical surfaces in the optical systems. However, making separate compensators to detect each aspherical surface is costly, lack versatility, and faces processing challenges. To solve the problem that different compensators are needed for various aspherical surfaces with different parameters, a method of interferometric surface test put was forward by using spatial light modulator (SLM) as a null-test compensator. This method combined a polarizing beam splitter and waveplates to construct a testing optical path, so as to achieve the measurement of aspheric surface errors. The interferometric testing method was validated by simulating the testing optical path of a field lens with concave aspherical surfaces on both surfaces on ZEMAX. In the meantime, the wavefront modulation error of SLM was simulated and analyzed through MATLAB. The simulation results indicate that the method can test different aspheric surface errors, and the wavefront modulation accuracy within the designed optical path reaches up to 0.008 3λ.