〔Abstract〕 Objective To study the effects of miR-146b-5p and E3 ubiquitin protein ligase(ZNRF3) on the process of hyperglucose-induced epithelial mesenchymal transformation(EMT) and mechanism in mice peritoneal mesoepithelial cells. Methods The mice in normal culture were the control group, and the mice with peritoneal fibrosis were induced by 4.25% glucose dialysate and 0.1 mg/kg lipopolysaccharide. The peritoneal tissues of mice were collected and Masson staining was used to observe the changes of collagen fibers in the peritoneal tissues. The expressions of α-smooth muscle actin(α-SMA) and type I collagen(COL I) were determined by immunohistochemistry. Western blot was used to detect epithelial cadherin(E-cadherin), α-SMA and COL I expression in peritoneal tissues. qRT-PCR was used to detect miR-146b-5p and E3 ubiquitin-protein ligase(ZNRF3) expression in peritoneal tissues. Dual luciferase reporter gene assays were performed to verify the relationship between miR-146b-5p and ZNRF3 targeting. Control mouse peritoneal mesothelial cells were isolated, then high glucose was induced to construct a mouse peritoneal mesothelial cell fibrosis model. The cells were divided into control group, model group, mimic-NC group, miR-146b-5p-mimic group and miR-146b-5p-inhibitor. Transwell chambers were used to detect cell migration and invasion ability. Western blot was used to detect the expression of EMT-related proteins. Results Compared with control mice, model mice showed thickened peritoneal tissue, increased collagen fibers, increased expression of α-SMA and COL I(P<0.05), increased expression of miR-146b-5p(P<0.05), and decreased expression of E-cadherin and ZNRF3(P<0.05). miR-146b-5p targeted to negatively regulate ZNRF3 expression. Cellular level results showed that the number of migrating and invading cells in peritoneal mesothelial cells increased(P<0.05), E-cadherin expression decreased(P<0.05), and Vimentin and N-cadherin expression increased(P<0.05) in model and mimic-NC groups of mice compared with the control group. Compared with model group, the trend of peritoneal mesothelial cell changes was more significant in the miR-146b-5p-mimic group of mice, and the cellular EMT process was inhibited in the miR-146b-5p-inhibitor group. Conclusion MiR-146b-5p can target ZNRF3 gene to promote high glucose-induced EMT process in mouse peritoneal mesothelial cells.