Thinfilms of lead tellurium selenide were evaporated on silicon substrates from a resource of PbTe0.92Se0.08 bulk crystal grown by Bridgman method. Xray diffraction (XRD), scanning electron microscope (SEM), and energydispersive analysis by Xray (EDAX) were used to characterize the structural and surface morphological properties, as well as chemical compositions of the thinfilms. The results indicate that thinfilms of lead tellurium selenide have a polycrystalline structure and a preferred orientation during the deposition. It was also revealed that the grains appear as rectangles. By comparison of the optical properties of the thinfilms deposited at different substratetemperatures, it was found that substrate temperature has an important effect on the infrared optical properties of thinfilms. The refractive index of the lead tellurium selenide thinfilms lies between 5.2 and 5.8, and the extinction coefficient is lower than 0.1. When the wavelength is greater than 6μm, the extinction coefficient of the thinfilms is as less as 10-3. It can be inferred that lead tellurium selenide is a potential material to be used in the infrared coatings.