Abstract： Aim To investigate the prognostic value of peripheral blood miR-30a in patients with sepsis complicated with a-cute respiratory distress syndrome(ARDS).Methods 100 patients with sepsis complicated with ARDS were selected as the re-search objects.According to the patients'outcome on 28 day,35 patients were selected into the death group and 65 patients were se-lected into the survival group.The differences of miR-30a,ERK protein and phosphorylated protein levels between the two groups were compared,and the prognostic value of miR-30a,ERK protein and phosphorylated protein levels in patients with sepsis complicat-ed with ARDS was estimated.Results The levels of miR-30a and the phosphorylated protein in the death group were significantly higher than those in the survival group(P＜0.05),and the ERK protein in the death group was significantly lower than that in the sur-vival group(P＜0.05).The combined diagnosis of miR-30a,ERK protein and phosphorylated protein had a high diagnostic specifici-ty.According to ROC curve analysis,the area under the curve of the combined detection of miR-30a,ERK protein and phosphoryla-ted protein was significantly higher than that of the single detection(P＜0.05).Conclusion Abnormal expression of miR-30a,ERK protein and phosphorylated protein in peripheral blood can be used as an important prognostic basis for patients with ARDS com-plicated by sepsis.