This study examined the effects of trifoliate orange extract (TOE) on inflammatory reactions at the time of an LPS shock by performing experiments on rats injected with trifoliate orange extract and in Raw 264.7 cell cultures, with the aim of developing a new anti-inflammatory medicine. The IL-1β, IL-6, and TNF-α concentrations were lower in all of the groups treated with TOE than in the control group after 5 h of LPS treatment. The IL-10 concentration was higher in the 300- ㎎/㎏ TOE group than in the control group after 2 h and 5 h of LPS treatment. The liver concentrations of cytokines IL-1β and IL-6 decreased more in the groups treated with TOE than in the control group and the IL-6 concentration did not differ significantly between the 100-㎎/㎏ TOE group than in the control group. The TNF-α and IL-10 concentrations did not differ significantly between the TOE groups and the control group. In the experiments involving Raw 264.7 macrophage cultures subjected to LPS shock, the productions of IL-1β, IL-6, and TNF-α decreased in all of the groups treated with TOE compared to the control group. The IL-10 concentration did not differ significantly between the groups treated with TOE and the control group. Together the findings of this study suggest that TOE contains functional substances that can influence inflammatory reactions.