The invention belongs to the field of spectrums, particularly relates to a method for calculating spectral characteristics of a binary laminated optical material, and in particular relates to a method for calculating reflectivity and transmissivity spectrums of a ZnS/ZnSe laminated infrared optical material. A transmission/reflection spectrum of an optical wave after passing through the binary laminated material is obtained by building a physical model of light transmitted in the axial direction of the laminated material and an optical noncoherent transmission theory; and a physical relationship between the basic physical properties and physical thicknesses of ZnS and ZnSe and transmission/reflection spectral characteristics is built. The method has universality on spectral calculation of the binary laminated material, and a theoretical basis is provided for optical wave energy modulation characteristics of the binary laminated material.