This study investigated the effects of oligonol intake on cortisol, interleukin (IL)-$1{eta}$, and IL-6 concentrations in the serum as well as body temperature after leg immersion into hot water. Thirteen healthy male volunteers participated in this study. Each subject received oligonol (100 mg) before leg immersion into hot water. Skin and tympanic temperatures were measured and mean body temperatures were calculated. Serum concentrations of cortisol, IL-$1{eta}$, and IL-6 were measured during and after leg immersion. Individuals who received oligonol had significantly decreased cortisol concentrations and serum levels of IL-$1{eta}$ and IL-6 compared to ones who did not receive oligonol. In addition, skin, tympanic, and mean body temperatures of oligonol group were maintained at lower degree overall recovery period compared with placebo group. These results suggest that oral oligonol intake before hot water immersion had a significant effect on inhibition of pyrogenic cytokine response and thermal suppression in healthy young men.