Objective: To investigate the clinical value of bedside pulmonary ultrasound (LUS) in acute respiratory distress syndrome (ARDS) in ICU. Methods: 60 suspected ARDS patients were examined by blood gas analysis, chest CT and LUS. 40 cases of ARDS were diagnosed by LUS. The sensitivity, specificity and accuracy of diagnosis of ARDS by LUS were analyzed. The ROC curve of diagnosis of ARDS by LUS score=18 was drawn and the area under the curve was calculated. According to Berlin criteria, ARDS patients were divided into two groups: group A (non-severe) and group B (severe). LUS score, EVLW and APACHE II score were compared between the two groups, and correlation analysis was made. According to the prognosis, the patients were divided into group C (death) and group D (survival). The LUS scores, EVLW scores and APACHE II scores of the two groups were recorded and compared. Results: The sensitivity, specificity and accuracy of LUS in the diagnosis of ARDS were 87.5%, 75.0% and 83.3%, respectively. The area under curve was 0.957, the standard error was 0.014, and the confidence interval was 0.029-0.985. The scores of LUS, EVLW and APACHE II in severe group were significantly higher than those in non-severe group (P<0.05). The results of LUS were positively correlated with the values of EVLW (r=0.763, P<0.05), and the results of LUS were positively correlated with APACHE II score (r=0.593, P<0.05). The LUS score, EVLW value and APACHE II score in the death group were significantly higher than those in the survival group (P<0.05). Conclusion: LUS can accurately diagnose ARDS, judge the condition and evaluate the prognosis. It has good clinical value.