The effects of two polarization components of different polarization states on the interference fringe contrast are investigated based on the principle of Michelson interferometer. Simultaneously, a Matlab-based interference fringe contrast calculation method is used to quickly evaluate the fringe image contrast. Finally, the relationship between the polarization components of different polarization states and the interference fringe contrast can be obtained by analyzing the experimental data. The results demonstrate that this research can be applied to either interference instruments or interference experiments. Introducing polarization modulation at the light source to obtain high-contrast interference fringe images will improve the measurement accuracy.