The immune response in animals and hu-mans is a biological defense mechanism against negative environmental factors. The immune system is a complex of organs and cells of the body, that reacts (protects) against foreign objects-protozoas and hel-minths. The aim of the study was to investi-gate the dynamics of cellular factors of the immune system of healthy minks, experi-mentally invaded with eimeriidosis against the background of specific immunocorrec-tive therapy. To study the dynamics of T-lymphocytes in the blood of animals, being at the specific immunocorrective therapy, a single-center prospective blind randomized comparative study was conducted in parallel groups. At the initial stage of the study, 56 male minks were isolated from the general population. The first group of clinically healthy animals was the control group. From the second to the sixth groups, animals were spontaneously infected with eimerias and isospores. Animals from the third and fifth groups were treated with coccidiostatic "Stop-coccid". Mink of the 4th and 6th groups received the drug "Ametherm 5%". Minks in the 5th and 6th groups after treat-ment with coccidiostatic were adninistered an immunomodulatory drug of plant origin "Phytodoc-immunostim". The 7th group served as an additional control and received a placebo-water with starch. Thus, the analy-sis of the results of the clinical study showed that the use of specific and immunocorrec-tive therapy has a positive effect on the dy-namics of T-lymphocyte levels in the blood of animals with eimeriidosis. In group 3, where infected minks were treated with "Stop-coccid", the level of T-lymphocytes increased by 35.8% to 41.1%; in the 4th group (administered "Ametherm 5%") the level of T-lymphocytes rose from 35.2% to 42.3%; in the 5th group (administered “Stop-coccid” and immunomodulator) the level of T-lymphocytes changed from 36.5% to 43,0% in the 6-th experimental group (treated "Ametherm 5%" and immunomodu-lator) the level of T-lymphocyte growth from 38.6% to 43.9 per cent.