OBJECTIVES: Asthma creates a heavy economic burden on Chinese patients and society. Therefore, it is important to consider the economic impact of alternative treatment options for asthma to ensure effective Health care resource allocation. METHODS: A retrospective economic analysis was conducted as part of a multicentre, randomized, open-label, 6-week comparative trial of salmeterol/fluticasone propionate combination product (SFC) 50/100 µg twice daily vs. budesonide 400 µg twice daily in 386 adults with asthma who were symptomatic despite treatment with inhaled steroids at doses of 500µg daily. Treatment effectiveness was measured in terms of successfully-treated weeks, defined as a >5% improvement in morning peak expiratory flow, episode-free days (a day without symptom and the need for rescue medication) and symptom-free days. Cost-effectiveness analyses were performed using direct Health care costs with sensitivity analysis analysis to test the robustness of the findings. RESULTS: SFC produced significantly higher (P<0.0001) proportions of successfully-treated weeks, episode-free days, and symptom-free days. Direct asthma management costs were similar between the two groups [US$13.2 for SFC vs.US$11.7 for budesonide per week]. The cost per successful-treated week was lower for SFC than for budesonide [$18.6 vs. $20.0 per week], as were the costs per episode-free day [$4.21 vs. $6.12 per day] and symptom-free day [$4.04 vs. $6.10 per day]. Incremental cost-effectiveness ratios showed that the additional costs to achieve additional benefits with SFC were minimal. Costs per additional successful-treated week, symptom-free day and episode-free day with SFC were $12.3, $1.1 and $1.26 respectively relative to budesonide. Sensitivity analysis showed that the results were stable over a wide range of assumptions. CONCLUSIONS: The results suggest that SFC 50/100µg bd. is a more cost-effective treatment than four-fold higher dose of budesonide ( 400µg bd.) in the management of asthma who are symptomatic on their existing dose of steroid.