Objective To analyze the risk factors of diabetic retinopathy (DR) complicated with diabetic nephropathy (DN) and their predictive values. Methods A total of 1969 cases with type 2 diabetes mellitus (T2DM) diagnosed in our department from May 2017 to May 2018 were recruited in this study. According to their clinical data, they were assigned into DR complicated with DN group (DR+DN, n=609), DR group (n=746) and without DR or DN group (non-DR+non-DN, n=614). Their blood glucose level, blood pressure and liver and renal functions were compared among the 3 groups. The risk factors for DR complicated with DN and their predictive values were analyzed. SPSS statistics 18.0 was used to perform the statistical analysis. Analysis of variance or Chi-square test was employed for different data types. Multivariate logistic regression analysis was used to analyze the risk factors for DR combined with DN. Receiver operating characteristic (ROC) curve analysis was applied to assess the predictive values for the obtained factors. Results Except the level of high-density lipoprotein cholesterol (HDL-C) and intima-media thickness (IMT) of left carotid artery, there were significant differences in other indices among the 3 groups (P<0.05). Logistic multivariate regression analysis showed that the protective factors for occurrence of DR complicated with DN was age (OR=0.966,5%CI 0.932-1.000; P=0.049), albumin (ALB, OR=0.872,5%CI 0.837-0.908; P<0.001) and statins (OR=0.400,5%CI 0.265-0.606; P<0.001), while, the risk factors were course of hypertension (OR=1.021,5%CI 1.005-1.037; P=0.011), systolic blood pressure(OR=1.018,5%CI 1.007-1.029; P=0.002), fasting blood glucose (OR=1.054,5%CI 1.002-1.108; P=0.040), triglycerides (OR=1.133,5%CI 1.021-1.256; P=0.019), low-density lipoprotein cholesterol (OR=1.355,5%CI 1.017-1.805; P=0.038), blood urea nitrogen (OR=1.124,5%CI 1.016-1.244; P=0.023), cystatin C (OR=2.466,5%CI 1.495-4.068; P<0.001), score of fundus oculi (OR=1.275,5%CI 1.088-1.494; P=0.003), thickness of left ventricular posterior wall (OR=1.306,5%CI 1.051-1.622;P=0.016) and carotid atherosclerotic plaque (OR=1.578,5%CI 1.051-2.370; P=0.028). ROC analysis revealed that cystatin C was the most significant predictor for occurrence of DR complicated with DN, with the area under ROC curve of 0.677. Conclusion In T2DM patients, the prevalence of DR complicated with DN is quite high, which is related to a variety of factors, and among them, cystatin C has the highest efficiency in the prediction.