Recently the older population, persons 65 years or older, is rapidly growing. This phenomenon brings about many problems in socio-economic and medical aspects. Prevalence of diabetes mellitus in the old population is also increasing. There is some difference in treating elderly diabetic patients when compared to young or middle aged diabetic patients. Although anti-diabetics agents are not different, we have to consider many things, such as, age, comorbidity, polypharmacy, health and socioeconomic status. Factors of geriatric syndrome needs to be considered. Physicians must recognize that these factors affect glycemic control and it is closely correlated with mortality. The target of glycemic control should be individualized in elderly diabetic patients according to their situation. In patients with multiple comorbidities or short life expectancy, avoiding hypoglycemia and less stringent glycemic control may be appropriate rather than intensive glycemic control. Recent trials with intensive glycemic control have failed to demonstrate decreased mortality with glycemic control and severe hypoglycemia was associated with increased mortality. In conclusion, most appropriate treatment should be determined by considering characteristics and side effects of anti-diabetic agents and individualized target goals in elderly diabetic patients.