This meta-analysis was performed to evaluate the difference of the therapeutic effi cacy and adverse effects of leukotriene receptor antagonist and theophylline added to inhaled corticosteroids in adult asthma. Databases were searched for studies published through Nov, 2010. Randomized-controlled trials containing inhaled corticosteroids plus leukotriene receptor antagonist and inhaled corticosteroids plus sustained-release theophylline for asthma therapy were selected. For each report, data were extracted to the outcomes analyzed: mean change in morning peak expiratory flow, mean change in evening peak expiratory flow, mean change in morning forced expiratory volume in 1 sec, mean change in daily short bete2-agonist use, asthma exacerbation and adverse effects. Four assessable trials including 182 asthmatic patients were identified. Inhaled corticosteroids plus leukotriene receptor antagonist was superior to inhaled corticosteroids plus theophylline therapy in improving morning peak expiratory flow in asthmatics (mean difference 19.08 [95% confidence interval 13.37-23.79] l/min, p<0.001) and morning forced expiratory volume in 1 sec in asthmatics (mean difference 0.09 [95% confidence interval 0.03-0.14] liter, p=0.001). In evening peak expiratory flow, daily short bete2-agonist use, asthma exacerbation and adverse effects, there was no significant difference between these two therapies (All p>0.05). Our meta-analysis showed that the combination of inhaled corticosteroids plus leukotriene receptor antagonist resulted in more improvement in both peak expiratory flow and forced expiratory volume in 1 sec in the morning than inhaled corticosteroids plus sustained-release theophylline in adult asthmatics. Further trials are necessary to evaluate the dominant effects of the former combination.