Chalcogenide glass is an excellent infrared optical lens material, but its thermal expansion coefficient is large. Compared with Si, Ge and other infrared optical materials, the chalcogenide glass lens produces larger residual stress in the coating process, and the shape changes after coating is large. The mechanical properties of the film can be improved by studying the stress in the film and optimizing the stress control method. In this paper, the residual stresses of different material coatings on the substrate were studied by measuring the variation of the substrate before and after coating on As40Se60 chalcogenide glass. At the same time, the thermal stress of As40Se60/ZnS/Ge/ZnS/Ge/ZnS/YbF3/ZnS infrared optical lens film chalcogenide was calculated and simulated by ANSYS software, which verified the rationality of the model. The axial and radial distributions of thermal stress in the film structure were analyzed. The results show that the thermal stress of the film structure is mainly concentrated in the film in the axial direction, and the thermal stress of the surface film is the largest. In the radial direction, the thermal stress is evenly distributed and suddenly drops at the edge. The relationships between thermal stress of the outermost protective film and deposition temperature, adjacent film layer, non-adjacent film layer and substrate were analyzed. The results show that the thermal stress of the protective film is proportional to the deposition temperature in the range of 110 ℃ to 200 ℃. The thickness and material of adjacent and non-adjacent films do not affect the thermal stress of the protective film. The thickness of the base will affect the thermal stress of the protective film.