Abstract: Objective This study was conducted to evaluate the potent immunomodulatory effects ofLactobacilli and their possible anti-allergic effects. Methods Lactobacillus plantarum LP45 (LP45), Lactobacillus plantarum La28 (La28), Lactobacillus plantarum6091 (6091), Lactobacillus rhamnosus GG (LGG) were orally administrated to male BALB/C mice, respectively for 28 d. The immune organ index, serum Th1 cytokines 〔interferon-γ (IFN-γ), interleukin-12 (IL-12)〕 and Th2 cytokines IL-6 of the tested mice were analyzed with ELISA after intervention. Furthermore, La28, 6901 were also orally fed to ovalbumin (OVA)-sensitized male BALB/C. The serum total IgE of the tested mice was analyzed with ELISA after intervention. Results No statistical difference was found in immune organ index among the tested four strains. La28 significantly decreased serum IL-6 of the tested mice after 14 d and 28 d compared to those in control ( P<0.05). After 28 d,6091 also significantly reduced serum IL-6 of the tested mice ( P<0.05). La28 significantly suppressed the increase of serum total IgE of the tested mice ( P<0.05). Conclusion The present study indicates that the immunomodulatory effects ofLactobacilli might be strain-dependent. Among the tested strains ofLactobacilli, La28 and 6091 may have possibility to influence the Th2 immunity of host animal. La28 may also posse potent ability to alter IgE mediated allergy by the way to affect Th1 / Th2 balance of host animal.