Objective To observe the efficacy of invasive ventilation (Ⅳ) in treatment of acute pulmonary edema (APE), and to explore the factors associated with prognosis. Method From March 2005 to December 2007, 23 APE patients, who were hospitalized in the EICU of People' s Hospital of Peking University and the con-ventional treatment and noninvasive ventilation were not effective, were treated by Ⅳ (PEEP 5～18 cmH2O). Blood pressure, heart rate, respiratory rate, and arterial blood gas values were recorded accurately before and after ventilation and compared with each other. Regression analysis was used to analyze the factors associated with prog-nosis. Resets Three hours after Ⅳ, the blood pressure, heart rate, respiratory rate, arterial blood gas were sig-nificanfly improved (P <0.01). Among the 23 patients, 11 survived, and the other 12 patients died. Nine pa-tients died of MOF. Among 16 patients with cardiac function Ⅲ-Ⅳ, 10 died. Among 15 patients with acute my-ocardial infarction, 9 died. Among 11 patients with renal insufficiency, 9 died. The multivariate logistic regression analysis showed that the reduced left ventricular ejection fraction, the lower mean arterial pressure, and the in-creased creatinine were the independent predictor of prognosis. Conclusions Invasive ventilation is an effective method of treating patients with acute pulmonary edema. Proper ventilation may improve the cardiac function and clinical symptoms, but it's not the fundamental measure for increasing cure rate. 1he renal insufficiency and heart failure are the independent predictor of prognosis.