<p>Patients with diabetes mellitus have decreased olfactory function as compared with healthy individuals. Hyposmia is more common in type 2 diabetes (DM2) and is characterized by a decreased ability to recognize odors accompanied by deterioration of olfactory memory, which reduces patients’ quality of life. The mechanisms of development of hyposmia require study in experimental models, though studies this type have not been conducted in most of the widely used animal models of DM2. The aim of the present work was to study olfactory function in a model of nicotinamide-streptozotocin-induced DM2 in rats using widely used behavioral tests of food-seeking efficiency using smell and olfactory preference. The DM2 model in male rats displayed a decrease in efficiency and an increase in the time spent seeking food objects by smell as compared with the control group, which may point to the development of hyposmia in diabetic animals. The results of the test for differentiation of the pheromonal mimetic isovaleric acid from biologically indifferent odorants did not reveal any between-group differences. The results obtained here indicate that the development of DM2 in adult rats mainly affects the functioning of the primary olfactory system rather than the operation of the supplementary system responsible for the perception of pheromones and pheromonal mimetics.</p>