In order to overcome the deficiency that the measurement function of the existing spectral Mueller matrix ellipsometer had been fixed and could not measure more physical quantities according to the experimental requirements, a new scheme was proposed to measure more physical parameters by combining multi-physical field optical simulation and wide-spectrum Mueller matrix ellipsometry measurement data. Taking film thickness measurement as an example, by comparing the matching degree of Mueller matrix obtained by the measured values of an ellipsometer and the simulated values of silicon dioxide films with different thicknesses and at different incident angles on a silicon substrate, the thickness value of the silica film with the smallest relative mean square error was obtained. The results show that the thickness of the film is in good agreement with the measured values. This study validates the feasibility and effectiveness of the combined method of spectral Muller matrix ellipsometry measurement and simulation.