The chalcogenide glasses are interesting materials for investigation of nanostructural properties possessing unique characteristics which are different from those in oxide and halide glasses, i.e. molecular (low-dimensional) structures, semiconductor properties, including a wide range of optical transparency, high refractive index n and specific electrical resistance. The aim of the work is to extend the research of nanostructuring properties of As2S3-Se nanomultilayers meaning the possibilities of direct, one-step surface relief formation by laser beam. As2S3-Se nanomultilayers were prepared by thermal evaporation of two compositions from two isolated boats on constantly rotated substrate at room temperature in one vacuum deposition cycle. Two wide rings overlap in the central part of substrate forming nanostructure. Overlapping part of samples contains alternating nanolayers of Se and As2S3. Outside and internal rings of layers on the substrate contain pure compositions of Se and As2S3 consequently. We present the study of photoinduced changes of optical properties of nanostructure As2S3-Se. On the base of the following parameters measured: optical transmittance and dispersion of refractive index we conclude that as-deposited nanostructures did not form solid solution from component material, but after illumination the photodiffution takes place.