Background: Nowadays asthma is considered to be an inflammatory disease characterized by airway hyperresponsiveness and pulmonary eosinophilia. Production of cytokines by bronchial epithelial cells may contribution to the local accumulation of inflammatory cells in patients with bronchial asthma. In many recent studies molecular biological methods have been used to investigate the role of cytokines in pathogenesis and new therapeutic targets of asthma. Objectives: We aimed to identify the clinical effects of Chuongsangboha-tang and the effects of Chuongsangboha-tang on serum cytokines in asthmatic patients. Materials and Methods: The subjects consisted of 36 patients with asthma who had been treated with Chuongsangboha-tang for four weeks. Chuongsangboha-tang is an herbal decoction which has been used of the traditional therapeutic agent of asthma. PFT, Quality of Life Questionnaire for Adult Korean Asthmatics (QLQAKA), blood eosinophil, serum IgE, Serum IL-4, IL-5, IFN- were checked before and 4 weeks after treatments. Results: Treatment with Chuongsangboha-tang for four weeks resulted in significant increase in FEV1.0%, PEFR%, QLQAKA. The blood eosinophil, serum IgE, IL-4 and IL-5 in asthmatic patients increased significantly compared to the normal control group, while the serum IFN-decreased significantly. Conclusions: This study shows that Chuongsangboha-tang has effects on improvement of pulmonary function and quality of life in asthmatic patients. Obviously, further research concerning this is still necessary.