Objective: To study the rules and the related risk factors of diabetic retinopathy(DR) in type-Ⅱ diabetes mellitus(NIDDM). Methods: 304 cases of NIDDM were investigated in detail about history, blood pressure, lens, fundus, and laboratory data were abtained. The incidence of DR and risk factors were then analyzed. Results: The DR incidence was 40.8%in 304 NIDDM patients, the background diabetic retinopathy (BDR) incidence was higher than that of proliferative diabetic retinopathy (PDR). The incidence of BDR and PDR was in a positive propotion with the age of patients, the coarse of NIDDM and the presence of hypertension and posterion subcapsular cortical opacity of tens. Conclusion: Long course of NIDDM, old age of patient, presence of hypertension and posterior subcapsular cortical opacity of the lens are the important risk factors of DR for NIDDM.