Background : Salmeterol, a new ${eta}_2$-adrenergic receptor agonist, is a long-acting bronchodilator and benefits patients with asthma who have nocturnal symptoms. We wished to assess the efficacy of inhaled salmeterol ($50{mu}g$ bid) compared to inhaled salbutamol ($200{mu}g$ qid) for the treatment of bronchial asthma, particularly nocturnal asthma. Method : We randomly assigned 35 patients (25 female and 10 male patients, 15 to 50 years old) to one of two treatment groups : one group received $50{mu}g$ of salmeterol twice daily and another did $200{mu}g$ salbutamol four times per day. And this study was performed as an open-label and the 6 weeks inhalation period. Results : Analysis of symptam score ; Day and night time symptom score showed significant difference between salmeterol and salbutamol Group (p<0.05). Number of days for additional bronchodilator requirements; The number of days and puffs for additional bronchodilator were lower in the salmeterol group in either day and night time (p<0.05). Pulmonary function test ; $FEV_1$ showed significant increase in salmeterol group compared to salbutamol group after 2 and 4 weeks inhalation period. Adverse effects ; We found no evidence of tolerance to the bronchodilating effects of salmeterol, and adverse reactions to all the treatments were infrequent and mild. Conclusion : For the management of bronchial asthma, salmeterol given twice daily is superior to salbutamol given four times daily.