Objectives : The aim of this study was to provide basic background information on stroke by evaluating various etiological factors on the basis that the onset time of cerebral infarction varies according to its cause. Methods : We studied hospitalized patients within 4 weeks after their ictus who were admitted at Kyunghee OMC, Kyungwon OMC, or Donguk Ilsan OMC from [month] $1^{st}$, 2005 to June $30^{th}$, 2007. We compared the general characteristics of acute stroke patients according to onset time. Results : Regardless of the onset time, the distribution of cerebral infarction patterns showed high SVO. The onset time did not show significant difference for average age, height, weight, BMI, waist measurement, hip measurement, or waist/hip ratio between onset during sleep and awakening. Patients whose stroke occurred while awake were more likely to have a past history of HTN, DM, ischemic heart disease, or atrial fibrillation but did not show significant difference according to their onset time. Conclusions : The above results show that the overall tendency of acute stage cerebral infarction patients varies according to their onset time. This study was carried out on the basis of previous findings that cerebral infarctions that occurred during sleep were more likely to have been caused by cerebral thrombosis, and strokes that occurred while awake were more likely to have been caused by cerebral embolism. However, there were no statistically relevant results, so a larger study group is needed to research the tendency of stroke patients.