The prevalence of diabetic ocular complications and the correlation between diabetic retinopathy and systemic factors were examined in 2,300 cases (4,600 eyes) with non-insulin-dependent diabetes mellitus. The prevalence of cataract was 66.7%, of retinopathy 37.0%, of refractive and accommodative change 6.2%, of glaucoma 1.9% (rubeotic glaucoma was 1.0%), of rubeosis iridis 1.5%, of iridocyclitis 0.8%, of extraocular muscle palsy 0.2%, and of ischemic optic neuropathy 0.1%. Duration of diabetes mellitus, HbA1C value, methods of diabetic control, age, diabetic nephropathy, diabetic neuropathy, hypertension, systolic blood pressure, diastolic blood pressure, and arteriosclerosis obliterans were related with diabetic retinopathy. We suggest that the management of diabetic patients needs sufficient attention in the cases with oral administration of medication, insulin therapy, and diabetic nephropathy.