Abstract: Regular consumption of kefir promotes beneficial physiological and therapeutic effects including stimulation of immune response. In this study, we investigated the immunomodulatory effects of kefir on peripheral mononuclear cells (PBMCs) derived from patients diagnosed with pulmonary tuberculosis (TB). PBMCs were isolated, treated with different concentration of kefir (1/20, 1/50, 1/100 and 1/200) and cultured for 4 days. The proportion of CD4+ and CD8+ cells was analyzed by flow cytometry and the production of Th1 cytokines IL-2 and IFN-γ and Th2 cytokines IL-4 and IL-10 was determined by ELISA. The results indicate that kefir slightly stimulated CD4+ as well as CD8+, but the effect was insignificant. Low doses of kefir significantly induced the secretion of IL-10 but not IL-2, IL-4, or IFN-γ. We conclude that kefir in a low concentration stimulates Th2 rather than Th1-type immune response and therefore works as an immunosuppressant for early diagnosed TB patients.