Corn has been used for a long time as a traditional remedy, as well as a food source. We previously reported that in vitro supplementation of corn water extracts enhanced the proliferation of splenocytes, compared to the control group. In this study, we examined the immunomodulative effect of a water extract of corn. Seven to eight weeks old mice(Balb/c) were fed an ad libitum chow diet, and were orally administrated a water extract of corn every other day, for four weeks, at two different concentrations(50 and 500 ㎎/㎏ B.W). Cytokine production(IL-2, IL-10 and IFN-γ) by macrophages stimulated with LPS or not stimulated with LPS was detected by ELISA assay using the cytokine kit. In an ex vivo study, the cytokines IL-2, IL-10 and IFN-γ were detected at 500 ㎎/㎏ b.w. supplementation group with LPS stimulation in all cases. Also, the ratio of IFN-γ to IL-10 was in the range of 0～3 with mitogen stimulation, such as con A and LPS. In conclusion, this study suggests that in mice, corn extracts may enhance immune function by regulating the cytokine production(IL-2, IL-10 and IFN-γ) of the activated macrophages.