Objective To observe the clinical effects of bi-level positive airway pressure ( BiPAP) combined with tiotropium bromide in the treatment of chronic obstructive pulmonary disease ( AECOPD) with acute exacerbation .Methods Sixty cases of AECO-PD with acute exacerbation were randomly divided into group A and group B , each consisting of 30 cases, and clinical analyses were made on them .The patients in both groups were given routine treatment , including oxygen breathing , spasmolysis , expectoration , anti-infection and BiPAP.At the same time, the patients in group B were administered with the above treatment couple with BiPAP inhala-tion agent, with a dosage of 18μg, once a day.Symptoms, pulmonary functions and blood-gas analysis were performed to see the effects and adverse reactions , and hospitalization days were also recorded accordingly .Results Total effective rate for group A was 73.33%, while the rate for group B was 93.33%, and statistical differences could be seen , when comparisons were made between them ( P<0.05 ) .Following treatment , symptom scores , pulmonary functions and results of blood gas analysis in the patients of both groups signif -icantly improved, as compared before treatment (P<0.05).The conditions of the patients in group B were obviously superior to those of the patients in group A, with statistical significance (P<0.05).For the average length of stay at the hospital , the patients in group B were obviously superior to those of the patients in group A (P<0.05).The incidence of adverse reactions for the patients in group B was low, with minor symptoms.Conclusion The effects of BiPAP combined with tiotropium bromide in the treatment of chronic ob-structive pulmonary disease with acute exacerbation were obviously superior to that by simple BiPAP therapy .Furthermore, the former was safer and more effective , which was worth further clinical extension .