Objective:To study the expression of miRNA-29c in type 1 diabetic patients with early nephropathy and its diagnostic value for early nephropathy.Methods:168 patients with type 1 diabetes who were treated in our hospital from Jan. 2019 to Mar. 2022 were retrospectively selected as the research subjects. According to the occurrence of nephropathy, they were divided into simple diabetes group (122 cases) and diabetic nephropathy group (46 cases). Serum miRNA-29c levels were detected by RT-PCR. The gender, age, course of disease, and serum miRNA-29c levels were compared between the two groups. Logistic regression was used to analyze the influencing factors of early nephropathy in patients with type 1 diabetes. The ROC curve was used to analyze the diagnostic value of miRNA-29c for early nephropathy in type 1 diabetes.Results:The course of disease, blood pressure (systolic blood pressure, diastolic blood pressure), HbA1c, TC and blood uric acid in early nephropathy group were higher than those in simple diabetes group, while albumin, total bilirubin and miRNA-29c were lower than those in simple diabetes group, and the difference was statistically significant ( P<0.05). Multivariate Logistic analysis showed: long disease duration ( OR=2.061, 95% CI=1.090-3.896), systolic blood pressure ( OR=1.143, 95% CI=1.023-1.279), diastolic blood pressure ( OR=1.151, 95% CI=1.022) -1.298), high HbA1c ( OR=1.317, 95% CI=1.049~1.653), high blood uric acid ( OR=1.306, 95% CI=1.028-1.659), low miRNA-29c ( OR=0.845,95% CI= 0.730-0.979) were the risk factors for early nephropathy in patients with type 1 diabetes ( P<0.05). ROC curve analysis showed that the cut-off value of miRNA-29c for the diagnosis of early renal disease was 0.952, the area under the curve (AUC) was 0.863 (95% CI: 0.801-0.925), and the sensitivity and specificity were 84.78% and 80.33%, respectively. Conclusion:Serum miRNA-29c in patients with early stage nephropathy of type 1 diabetes is in a low expression state, which is an influencing factor for early stage nephropathy in patients with type 1 diabetes, and has a good diagnostic value for early stage nephropathy.