Zinc selenide crystals are increasingly applied in the infrared, LED, and fiber optic technology as the detectors of X-rays and elementary particles. The analysis of ZnSe photoconductivity can facilitate identification of specific technological conditions necessary to obtain samples with preset parameters. After preliminary optical excitation of a certain wavelength of high-resistance ZnSe, there is a splash in the relaxation curves of the photocurrent observed at irradiation with light of the other wavelengths from the region of impurity absorption.