Objective To observe and compare the effect of the treatment using NIPPV (non-invasive positive pressure ventilation)or Ⅳ (invasive ventilation)on the drowned with ARDS (acute respiratory distress syndrome). Methods 63 patients into two groups-group A (NIPPV) and group B (Ⅳ). The effects of the two ventilations wrer obserred. Results pH, PaO2, PaCO2 and HR, RR in the two groups were all improved ( P ＜0.05)after machinery ventilating for 0.5 h,1 h,4 hs and 12 hs. HR and RR in group B dropped faster than those in group A after machinery ventilating for 0.5 h, and 1 h, but consistent for 4 hs. This concerned muscle relaxants or the sedative anesthetics used when intubating in group B. The time of machinery ventilating and the treatment of group A was shorter than thoseof group B ( P ＜ 0.05 ). The average expense of group A was smaller than group B and the pneumonia formation rate of life-support machine in group A was lower, too. Two groups were not obviously different in cure rate. Conclusion NIPPV and Ⅳ have a good treatment result for the drowned with ARDS, but NIPPV is better than Ⅳ.