Objectives : Macrophage has an important innate defense role in the immune system. When we are infected with pathogens, macrophage ingests them through phagocytosis or endocytosis, and then secretes many cytokines, such as IL-1, IL-6 and $TGF{alpha}$, which are regulators of immune responses. The aim of this study is to determine how Samjunghwan effects the expression of cytokine and other immune-related genes in macrophages. Methods : Cells were treated directly with Samjunghwan and/or LPS at regular intervals. Total RNA of cells was isolated using TRIzol reagent, and the changes in cytokine gene expressions were investigated using RT-PCR, western blot and ELISA. Results : $IL-1{alpha},;IL-1{eta}$ and COX-2 genes were inducibly expressed specifically by Samjunghwan in macrophage. Especially, $IL-1{eta}$ gene was induced most strongly by treatment with Samjunghwan. Over time, treatment with Samjunghwan showed that the expression levels of $IL-1{alpha};and;$IL-1{eta}$ genes increased from 1 to 4h, and then decreased from 4 to ISh. However, the expression level of COX-2 gene increased continuously up to 11h. $IL-1{alpha},;IL-1{eta}$ and COX-2 genes were expressed synergistically by a simultaneous treatment of both Samjunghwan and LPS in macrophages. Secretion levels of translated $IL-1{eta}$ increased continuously up to 11h. Conclusions : Though this study is only a start in the investigation of the efficasy of Samjunghwan, these results suggest that Samjunghwan has positive effects on immune responses.