Introduction: Lacunar infarction (Lac) and hypertensive intracerebral hemorrhage (ICH) are known as cerebral small-vessel disease in which hypertension plays a pivotal role in the development of pathology. However, it is unclear why some patients suffer from cerebral infarction and others bleed. We compared the background of these two groups, and examined differences and similarities between them. Methods: Between February 2008 and January 2013, 1149 patients were admitted to our institution within 1 week after the onset of stroke. A database was prospectively constructed with this consecutive patients’ cohort and data were analyzed retrospectively. Among the patients, 138 had Lac and 109 had ICH. Results: Age, sex, and BMI were not different between the groups. Medication prior to the onset of stroke was more common in Lac than in ICH (77.5% vs. 55.1%; p<0.001). The frequency of antiplatelet therapy, blood pressure-lowering therapy, and lipid-lowering therapy was not different between the groups. Treatment for diabetes mellitus (DM) was significantly more frequent in Lac than in ICH (29.0% vs. 8.3%; p<0.001). Calcification of the aortic arch was significantly more common in Lac than in ICH (62.2% vs. 43.3%; p=0.009). Smoking, past history of stroke, and familial history of stroke were not different between the groups. Left-sided stroke was significantly more common in Lac than in ICH (63.8% vs. 50.4%; p=0.004). On admission, triglycerides, total cholesterol (Chol), HDL-Chol, LDL-Chol, total protein, serum albumin, and blood sugar levels were not different between the groups. HbA1c levels on admission were significantly higher in Lac than in ICH (6.4+/-1.3% vs. 5.9+/-1.0%; p=0.004). Conclusions: Lac and ICH have similar backgrounds. However, left-sided stroke, calcification of the aortic arch, and a medical history of DM are more common in Lac than in ICH patients. HbA1c values on admission are higher in Lac than in ICH patients. This suggests that there are subgroups of Lac in which the pathological process is different from that in ICH. Therefore, endothelial damage induced by DM may play a role in some patients with Lac, and left-sided propensity and a tendency for aortic arch calcification suggest that some aortogenic embolisms may be diagnosed as Lac.