Abstract: Objective: To compare the role of non-invasive pressure support ventilation (NIPSV) and continuous positive airwaypressure(CPAP) in cardiogenic pulmonary edema obstructive patients. Methods: A prospective，randomized，controlled study wasperformed in an emergency departments，123 patients were assigned Objective: To CPAP(n = 54) and NIPSV(n = 69) groups. The mortality，tracheal intubation rate and mechanical ventilation time were compared. Results: There were no significant difference about the mortality and intubation rate between the two groups(P ＞ 0. 05). The mechanical ventilation time in NIPSV group was significantly shorter than that in CPAP group(P ＜ 0. 01). The mortality was higher in CPAP group with hypercarbia than that in NIPSV group(P ＜ 0. 05).Conclusions: The mortality and rate of reintubation of CPAP and NIPSV was similar in the mortality and intubation rat. When the cardiogenic pulmonary edema obstructive patients were accompanied with hypercarbia，NIPSV was more effective than CPAP.