Objective: To investigate the significance of microRNA (miR)-216a, miR-324-5p, miR-29a expression in peripheral blood in patients with acute pancreatitis (AP) and their correlation with liver injury. Methods: It was a case-control study design. To select 130 AP patients admitted from June 2017 to May 2019 in the First People's Hospital of Shangqiu, and the patients were divided into mild AP group (MAP group) and moderately severe AP group (SAP group) according to the disease severity, or 54 patients in the liver injury group (20 were MAP and 34 were SAP) and 76 in the non-liver injury group(all were MAP) according to liver injury. And another 40 healthy volunteers were selected as the healthy group. The expressions of miR-216a, miR-324-5p and miR-29a in peripheral blood of MAP group, SAP group, healthy group and liver injury group, non-liver injury group were compared, and the correlation between the miRNA levels and clinical indexes was analyzed. The predictive value of miRNA levels in peripheral blood for AP complicated with liver injury was analyzed by receiver operating characteristic (ROC) curve. Results: The levels of miR-216a and miR-29a in MAP group and SAP group were higher than those in healthy group, and the level of miR-324-5p was lower than that in healthy group (all P< 0.01). The levels of miR-216a and miR-29a in SAP group were higher than those in MAP group, and the level of miR-324-5p was lower than that in healthy group (all P< 0.01). Balthazar CT Score, acute physiology and chronic health evaluations (APACHE Ⅱ) score, C-reactive protein level, length of hospital stay were positively correlated with the levels of miR-216a and miR-29a in peripheral blood (all P< 0.05), and negatively correlated with the levels of miR-324-5p ( P< 0.05). The levels of miR-216a and miR-29a in the peripheral blood in the liver injury group were higher than those in the non-liver injury group, and they were higher inSAP patients than those in MAP patients in the liver injury group (all P< 0.05). The level of miR-324-5p in the peripheral blood in the liver injury group was lower than that in the non-liver injury group, and it was lower in SAP patients than that in MAP patientsin the liver injury group (all P< 0.05). The area under ROC curve of miR-216a, miR-324-5p, and miR-29a in peripheral blood to predicate the AP complicated with liver damage was 0.694, 0.750 and 0.814, respectively. Conclusions: The levels of miR-216a and miR-29a increase in peripheral blood and the level of miR-324-5p decreases in patients with AP, and they are closely related to Balthazar CT score, APACHEⅡ score, C-reactive protein and length of hospital stay. The levels of miR-216a, miR-324-5p, miR-29a has certain predictive value for AP with liver injury, of which miR-29a has the highest predictive value.