Objective To investigate the influence and effect of treating with low dose roxithromycin on airway inflammation in asthma who have been smoking patients .Methods Forty-six patients with mild to moderate asthma who had been smoking were assigned to group A and group B randomly .The patients in group A received inhaling salmeterol/fluticasone(50/250 μg) ,one puff bid ,2 times/day .The patients in group B treated with oral roxithromycin dispersible tablet 0 .15 g/d combining with inhaling salme-terol/fluticasone(50/250 μg) ,one puff bid ,2 times/day .The patients of two groups had been treated for 4 weeks .The lung func-tion ,cells and interleukin-8(IL-8) in induced sputum of patients in the two groups were measured before and after treatment .Results There was negative correlation between the FEV 1% and the number of eosinophile granulocyte ,neutrophil and the concentration of IL-8 in induced sputum of the patients(P<0 .01) .The number of neutrophil ,eosinophile granulocyte and the level of IL-8 of the patients in group B decreased more than those in the group A after 4 weeks of treatment(P<0 .05) .Furthermore the PEF and FEV1% of the patients in group B were ameliorated significantly than those in group A (P<0 .01) .Conclusion The treatment of roxithromycin combining with salmeterol/fluticasone on patients with asthma who smoke can not only reduce the number of eosino-phile granulocyte ,neutrophil and the level of IL-8 in induced sputum significantly ,but also ameliorate the PEF and FEV1% of them significantly .