OBJECTIVE： To observe the clinical efficacy and safety of doxofylline combined with recombinant human interferon α1b for prediatric moderate and severe bronchiolitis. METHODS： 170 children with moderate and severe bronchiolitis were divided into treatment group and control group according to random number table， with 85 cases in each group. Both groups were given conventional treatment. Control group was additionally given compression aerosol inhalation of Recombinant human interferon α1b for injection 2 μg/kg added into 0.9％ Sodium chloride injection 3 mL， bid. Treatment group was additionally given Doxofylline for injection 5 mg/（kg·d） added into 5％ Glucose injection 50 mL， ivgtt， qd， on the basis of control group. A treatment course lasted for 5 d， and both groups received 1 course. The total effective rates of 2 groups were observed as well as clinical symptom severity score before and after treatment and the occurrence of ADR before and after treatment. RESULTS： The total effective rate of treatment group was 97.65％， which was significantly higher than 88.24％ of control group， with statistical significance （P＜0.05）. Before treatment， there was no statistical significance in clinical symptom severity score between 2 groups （P＞0.05）. After 3 d and 5 d， clinical symptom severity score of 2 groups were decreased significantly， and the treatment group was significantly lower than the control group， with statistical significance （P＜0.05）. Adverse reactions occurred in 1 patient of treatment group and disappeared after slowing down dripping speed. No other obvious ADR was fourd in 2 groups.  CONCLUSIONS： Doxofylline combined with recombinant human interferon α1b show significant therapeutic efficacy for prediatric moderate and severe bronchiolitis， and can significantly improve clinical symptoms with good safety.