Cheonggeumganghwa-tang(CGT) has been used for the purpose of prevention and treatment of bronchial asthma and allergic asthma in Korea. To investigate the biological effect of CGT, the author examined cytotoxicity and inflammatory cytokines secretion with human mast cell line, HMC-1. HMC-1 was stimulated with phorbol 12-myristate 13-acetate (PMA) and calcium ionophore A23187. CGT by itself had no effect on viability of HMC-1. The effects of CGT on the secretion of tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-6 from HMC-1 were evaluated with enzyme-linked immunosorbent assay (ELISA). CGT (1 ㎎/㎖) inhibited PMA plus A23187 -induced TNF-α and IL-6 secretion, by 93.86 ± 2.05%, 68.69 ± 2.86%, respectively. CGT also inhibited the NF-κB (p50) expression. Taken together, these results suggest that CGT inhibit the production of inflammatory cytokines in HMC-1 cells through blockade of NF-κB activation.