Association analysis showed that after adjusting for age, sex, duration of diabetes, body mass index, HbA1c, blood pressure and albuminurea creatinine ratio and insulin treatment, age at diagnosis (OR 0.888, 95%CI 0.870–0.907, p = 0.00) and postprandial C-peptide (OR 0.920, 95%CI 0.859–0.937, p = 0.00) are the independent associated factors of DR in Chinese type 2 diabetes. Here, INS is linked to diabetes mellitus.