The complications af diabetes mellitus is well establshed as a leading cause of death, even though the insulin has contributed in great deal in cantrolling diabete., Therefore we have studied on the inicdence ef diabetic symptoms and complications among the 5.601 diabetes visited to the Diabctic. Clinic of S,N.U Hospital from the January, 1957 to June, 1977, and the followlng results were observed. The frequent symptoms were polydipsia, fatigue, neuropathy,weight loss, and impotance in sequence. 2. As the metabolic complication, diabetic ketoacidlosis, and cataract had a frequency of 1.2% and 9.9%, respectively. 3, As the vascular coirnplication.Hypetension had a frequency of 37.9%, perpheral vacular disease 3, 0%, coronary artery disease 2.2%, retinopathy 34.4% and nephorpathy 24.5% respectively. 4. As of neuropathy periphal nenropthy had a frequency of 32.7%, and autonomic neuropathy 12.8% respectively. 5. The frequency of infection was 28.0% of all diabetic, As of infections, tuberculusis had a frequency of 15.4%. 6. The retinopathy and neropathy were increased according to the duration of disease. The frequencies of the retinopathy nephropathy and infections were also increased in the groups with high blood sugar levels. 7.Cmpared to the previous results, the frequencies of hypertention, neuropathy, nephroplthy and cataract were increased.