BACKGROUND : Socheongryong-Tang(小靑龍湯, SCRT), a herbal medicine, has been widely used for the control of respiratory disease in Eastern countries. Recent years SCRT was known as anti-allergic agent. However, its therapeutic mechanisms, especially an inhibitory effect on inflammatory cell infiltration and airway remodeling in allergic asthma are unclear. METHODS : We investigated the effects of SCRT on levels of IL-4, and IFN-g using flow cytometric analysis and infiltration of inflammatory cells in bronchoalveolar lavage fluid(BALF) using cytospin methods in allergen-induced asthma. RESULTS : SCRT decreased levels of IL-4, a Th2-driven cytokine. But INF-g, a Th1-driven cytokine, was not changed. With SCRT treatment, infiltration of inflammatory cells showed reduced tendency. CONCLUSION : In conclusion, we demonstrated that regulation of Th1/Th2 imbalance may be one of mechanism contributed to reduction of inflammatory cell infiltration.