Objectives To investigate the role of IL-17 and IL-23 in pathogenesis of bronchiolitis, the influences of atopy on bronchiolitis, and provide the basis for the treatment and prognosis of the different physical in infants with bronchiolitis. Methods The blood samples of 60 cases of infants with bronchiolitis were collected as bronchiolitis group, and 20 cases of health children were enrolled as control group.Bronchiolitis group included 18 cases of children with atopy as atopy group and 42 cases of children without atopy as non-atopy group.Levels of IL-17 and IL-23 in peripheral blood were determined by solid sandwich enzyme-linked immunosorbent assay (ELISA) technique, and statistical analysis. Results 1)There were great differences in IL-17 and IL-23 among bronchiolitis group(15.79±4.82, 34.21±14.82) and control group(11.67±2.61, 23.89±7.15).The levels of IL-17 and IL-23 were clearly higher in bronchiolitis group than those of control group(P＜0.000 1).2)The levels of IL-17 and IL-23 were clearly higher in atopy group(21.07±4.81, 47.76±17.95) than those of non-atopy group(13.52±2.48, 27.89±5.59) (P＜0.000 1).3)There were clearly a positive correlation between the levels of IL-17 and IL-23 for bronchiolitis(P＜0.05). Conclusions IL-17 and IL-23 may be participate pathogenesis of bronchiolitis.The atopic children with bronchiolitis could be more easier development of asthma in the future, and early intervention should be emphasized to prevente asthma.