Abstract: Infrared optical film is widely used in Infrared optical systems. Its refractive index is an important parameter of the optical film design. Because of the special requirements of space application,infrared optical film is usually used in low temperature. The refractive index of infrared optical film material is always changed with the temperature,and this characteristic have a great effect on the manufacture of the infrared optical film. In this paper,the temperature characteristic of infrared optical film was discussed,and the basic theory of the refractive index dispersion was summarized. And we discussed the tendency of the development of the temperature characteristic.