Aim. To develop the testing algorithm in conditions of radial eight-arm maze and to study the effect of preparation “Cycloferon®” on cognitive processes in experimental animals in conditions of repeated training. Materials and methods. The study was conducted on experimental animals – white outbred male rats (n = 21) aged 8–9 months using the original method. “Radial eight-arm maze” was used as experimental laboratory device. During the experiment, to activate searching behavior, daily nutrition regime was reduced by 15–20 %. To fortify, milk product “Thickened milk” was used. At the first experimental stage, the animals received a typical vivarium ration. During the second part of this study, the rats underwent repeated training after taking “Cycloferon®”, calculated for each rat by the mass – 0.77 mg per 100 g of the animal body mass; after that the rats’ spatial memory was assessed. Results. Taking into account the results of the second part of experiment, statistically significant tendency to increase was revealed among animals with positive result of testing with one-sided Fisher criterion (p = 0.037). No correlation between taking “Cycloferon®” and the number of repeated entering of the arms and the total number of entering of the arms was detected (p > 0.05) that proves the formation of purposive movement. Conclusions. A reliable tendency to increase in the number of animals, trained during the repeated testing against the background of using “Cycloferon®”, which possesses immunomodulating effect as well as antioxidant action, confirms the actuality of applying the offered method while studying cognitive effect of substances, requiring long-term introduction.