Phase compensator is a key element in the polarized interferometer, whose stability has a directive influence on the reliability of the polarized interference spectroscopy. The specification of the phase compensator such as the relative sensitivity of optical path difference, the tilted error tolerance of optical wedge, the oblique incidence angle error tolerance and the temperature adaptability were studied, and the corresponding calculated formulas were derived. The anti-interference ability of the moving optical wedge is 2/Δnsinθ times stronger than the classical Michelson interferometer. The ability of the moving wedge to resist the inclination is 1.75/Δn times higher than classic Michelson interferometer. After light′s incidence with small angle, there are no additional optical path. The greatest optical path distance error of the phase compensator is 1.8 μm when the temperature changes from ―20℃ to 85℃,which has a good thermal stability. The angle of the wedge is also an important parameter to affect the phase compensator. If setting the angle of the wedge as 30°, a good balance between performance, size and cost may be achieved. The birefringence difference of crystal material is smaller than one, so the stability advantages of the polarized interferometer are very obvious which build up a good basis for its field application with complicated surroundings.