Abstract： Objective:To investigate the expression level and clinical value of serum miR-148a-3p and miR-551b-5p in patients with acute pancreatitis (AP).Methods:The clinical data of 152 patients with AP admitted to Danzhou people's Hospital from January 2017 to September 2020 were selected. According to the severity of their illness, they were divided into MAP group ( n=70), MSAP group ( n=40), and SAP group ( n=42). The SAP group was divided into survival group ( n=25) and death group ( n=17) according to the prognosis of the patients. Another 50 healthy people were selected as the control group. Fastening venous blood was collected on the day of onset, and the expression levels of serum miR-148a-3p and miR-551b-5p in each group were detected by real-time quantitative PCR. The receiver operating characteristic curve (ROC) was drawn and the area under the curve (AUC) was calculated. The expression levels of serum miR-148a-3p and miR-551b-5p were analyzed to evaluate the prognosis of SAP. The correlation between serum miR-148a-3p and miR-551b-5p expression levels in SAP patients was analyzed by Pearson method. Results:The expression levels of serum miR-148a-3p (3.18±1.27 vs 0.96±0.28) and miR-551b-5p (1.94±0.85 vs 0.51±0.12) in AP group were significantly higher than those in control group ( P<0.001). The expression levels of serum miR-148a-3p (4.36±1.70 vs 2.84±1.10, 2.50±0.92) and miR-551b-5p (2.80±1.04 vs 1.68±0.53, 1.42±0.45) in SAP group were significantly higher than those in MSAP group and MAP group ( P<0.001). The expression levels of serum miR-148a-3p (5.30±1.95 vs 3.47±1.40) and miR-551b-5p (3.62±1.37 vs 2.08±0.91) in death group were significantly higher than those in survival group ( P<0.001). ROC curve analysis showed that the AUC of the combination of miR-148a-3p and miR-551b-5 in judging the prognosis of SAP was significantly higher than that of the single index of miR-148a-3p and miR-551b-5[0.943(95% CI0.886-0.997) vs 0.860(95% CI0.797-0.924), 0.822(95% CI0.795-0.880)], with a sensitivity of 98.3% and specificity of 84.6%. Correlation analysis showed that there were positive correlation between the expression level of serum miR-148a-3p and miR-551b-5p in SAP patients ( r=0.835, P<0.001). Conclusions:The expression levels of miR-148a-3p and miR-551b-5p in serum of AP patients were significantly increased, and the combined detection of miR-148a-3p and miR-551b-5p had a good value in judging the prognosis of SAP.