The article presents the results of a study of the corrective effect of drugs based on interferons on the cellular immunity of newborn piglets on an industrial pig breeding farm. In neonatal period, the immune system development in animals doesn’t reach functional maturity, and immunocompetent cells have low functional activity. In regulation of the immune system, interferons play a significant role in formation of the immune response, proliferation and differentiation of lymphocytes, as well as the activation of mononuclear phagocytes. In order to improve the body immune status, there’ve been designed species-specific drugs based on rIFNs with immunomodulatory properties. For the experiment, 3 groups of newborn piglets were selected. Piglets of experimental group I at the age of 3-5 days were injected intramuscularly with biferon-S at a dose of 0.1 ml/kg twice, with an interval of 24 hours, piglets of group II – once with prostimul at a dose of 0.1 ml/kg. Piglets of group III (control) were not treated with drugs. It has been established that the application of biferon-S, containing rpIFN–alpha and -gamma, and prostimul, containing recombinant type I cytokine and vitamins A, E and C, in the first days of piglets' life, promotes an increase in cellular immunity, the absolute and relative number of lymphocytes, Tlymphocytes, T-suppressors and T-helpers, the content of active phagocytes, their absorptive and metabolic activity, due to the presence of rpIFN in the drugs that rapidly induce the system of endogenous interferons, cellular and humoral immunity, and in prostimul –vitamins A, E and C, possessing antioxidant properties. A more significant corrective effect on cellular immunity has been exerted by biferon-S, containing not only interferon alpha, but also gamma, which is cytokine - a regulator of immune responses, an inducer of cellular immunity.