Objective To observe the efficacy and safety of the intravenously applied ambroxol in the treat-ment of bronchiolitis. Methods 85 eases of bronchiolitis were randomly divided into two groups. 30 eases of control group were treated with common therapy ,55 cases of treatment group were treated with the ambroxol(7.5mg) each time, Ivgtt bid,in addition to common therapy,and the treatment course was 5 days. The improvement of the cough,pant and sputum for the patients, and the untoward reaction for the drug were observed. Results The total effective ratios were 96.4% in treatment group and 80% in control group. There were significant differences between two groups(X2 = 4.33, P < 0.05). One case vomited slightly in treatment. Conclusion The intravenous application of ambroxol in treatment of bronchiolitis was highly effective and safe.