The inflammatory response is one of the first defenses our body has to fight against potential endangerments. It plays a critical role in host defense, clearing and slowing the infection in the case of microbial invasion. During an inflammatory response, a variety of cytokines are produced by cells and trigger or enhance the specific inflammation response. TNFα, one of these factors, plays a crucial role in many immune and inflammatory processes, such as proliferation, apoptosis, necrosis, and cell survival. It acts in orchestrating the cytokine cascade and the major regulator of inflammatory cytokine production. Abnormality of TNFα signaling leads to many diseases, including rheumatoid arthritis, psoriasis, Crohn's disease, atherosclerosis and cancer. Due to the importance of TNFα, regulating TNFα activity is a key to treat the related diseases. There is a long history of using medicinal herbs to treat diseases related to inflammation. We searched for ingredient that has the ability to inhibit TNFα, we examined AO herbal extract, containing 10 individual herbs and most of these herbs have anti-inflammatory activity within humans. We have tested the anti-inflammatory ability of AO herbal extract on mice. Furthermore, we used macrophage cell from young mice and found that AO extract has the ability to reduce the inflammation by inhibiting TNFα level.