The principles of the new static polarization wind imaging interferometer and the light beam splitting of the four-sided pyramid prism were briefly introduced. Both the light ray’s transmitting direction and the transmitted point coordinates in the section of the prism were deduced by the ray tracing method. When the parallel ray had passed through the four-sided pyramid prism, the relation between the incidence angle and the deviation angle was calculated, the relation between the incidence angle and the transmissivity was also calculated. All the above relations were simulated by the computer. According to the parameters of the static polarization wind imaging interferometer, both the angle between the side and the base and the length of the base were determined. This research was very important to the design and manufacture of the static polarization wind imaging interferometer.