In this study we investigated the effect of medical history on the incidence of stroke in Korean population. 217 stroke patients were enrolled as a case group. 160 non-stroke patients and 146 normal and non-stroke patients were enrolled as a control and a normal group, respectively, from Jul. 2005 to Mar. 2007. Stroke patients were hospitalized within 2 weeks after the onset of stroke. Medical history was gathered by interviewing each patient. Clinical data were analyzed using SAS software (ver 9.1). Hypertension and diabetes mellitus (DM) were statistically significant in a case group when compared with control and normal groups. Other parameters, such as transient ischemic attack, hyperlipidemia, ischemic heart disease, facial palsy, migraine, and hypochondria, did not show any statistical significance. The same association pattern was observed in the ischemic stroke patients of case group. On the other hand, hemorrhagic stroke patients of case group showed a significant difference in DM when compared with other subject groups. More efficient therapeutic strategy should be considered for patients with medical history, especially hypertensin and DM, to reduce the stroke incidence in Korean population.