The utility model discloses a refraction type infrared optical system for supersonic guidance, which comprises a fairing, a first positive power meniscus lens, a second negative power meniscus lens, a third positive power meniscus lens, a fourth double convex lens, a fifth negative power meniscus lens, a sixth positive power meniscus lens, a Dewar flask window, a filter plate, a cold diaphragm and a detector array. The refraction type infrared optical system is characterized in that the entrance pupil position is designed at the fairing by using secondary imaging, so that incident light from different viewing fields enters an imaging system from the same position of the fairing, the optical system is subjected to the same interference from infrared backgrounds of different viewing fields in a pneumatic environment and the influence of the pneumatic heat radiation effect on the uniformity of a mirror surface is reduced. Meanwhile, the turbulent flow mixing layers of incidents light from different viewing fields, which pass through the surface of the fairing are the same, so that the pattern distortion due to the change of gas density gradients of the mixing layers under different viewing fields is reduced and the imaging quality is improved.