The objective of this study was to evaluate the effect of fermented Kalopanax pictus (KP-F) on macrophage activation and its effect as a competitive inhibitor of LPS and inhibitory effect on endotoxemia. The results showed that KP-F could activate macrophage in a dose-dependent manner, and KP-F was confirmed to act as a ligand for TLR4. Also, it was found that KP-F did not exhibit the same biotoxicity as LPS in intraperitoneal injection, and that it could suppress the neutrophil migration induced by LPS administration. In normal mice, the body weight, tissue weight, and amount of nitrite and pro-inflammatory cytokines in serum showed no significant changes with KP-F diet for 2 weeks, confirming that administration of KP-F in normal mice did not lead to over activation of immune response and biotoxicity. In the mouse model of endotoxemia induced by LPS and D-galactosamine(D-GalN) in sub-lethal dose, the diet of KP-F effectively inhibited the amount of nitrite and cytokines in the blood, and thus was found to be able to relieve the hepatic and kidney injury. In addition, in the endotoxemia mouse model induced by LPS and D-GalN of lethal dose, the survival rate was increased by KP-F diet in a dose-dependent manner.