Xenobiotics, including salts of heavy metals, determine the development of pathology of individual organs and systems of the body. Adrenal hormones occupy a key place in the regulation and maintenance of the organism basic functions. The study of morphological, biochemical and immunohistochemical changes in the adrenal cortex of pubescent male rats at exposure to the complex of heavy metal salts remains an actual aspect of modern morphology. The experiment involved 24 white adult male rats weighing 250–300 g, aged 7–8 months. The animals of the experimental group consumed ordinary drinking water saturated with a combination of heavy metal salts (Zn, Cu, Fe, Mg, Cr) for 60 days. Histological, biochemical (determination of the content of hormones COR – cortisol, DHS – dehydroepiandrosterone sulfate) and immunohistochemical (determination of the expression of proliferation marker Ki-67) methods were used. Long-term consumption of the combination of heavy metals salts by mature rats leads to thickening of the stromal component of the gland, the rupture of capillaries and the violation of rheological properties of blood. Chromatin condensation, its marginal location, and initial stages of necrobiotic changes have been found in the spongiocyte nuclear apparatus. For endocrinocytes of the zona glomerulosa and zona reticularis of the gland, a slight increase in proliferative activity has been revealed, while cells of the zona fasciculata were non-reactive. These results correlate with the results of biochemical research, according to which hormones of the zona reticularis – DHS were actively involved in the formation of adaptive reactions in the body of experimental animals at the 60-day period of administration of the complex of heavy metals salts. The results of complex studies indicate a weakening of the secretory activity of cells of the zona fasciculata, which adversely affects the development of compensatory-adaptive processes in the body and the course of the general adaptation syndrome in response to the action of the damaging agent.