Our assumption that blood pressure (BP) in supratentorial hypertensive intracerebral hemorrhage patients does not differ significantly according to the hemispheric laterality has never been verified before. This study was carried out to explore the possibility of hemispheric BP differences and whether this might influence the outcomes. A review of the charts/radiographic images of 281 patients with putaminal/thalamic hemorrhages diagnosed within 6 h of symptom onset was performed. Immediately after arrival, they received a continuous intravenous nicardipine infusion to lower and maintain systolic BP (SBP) between 120 and 160 mmHg. They were quadrichotomized as follows: left putamen (LP, n=89), right putamen (RP, n=69), left thalamus (LT, n=68), and right thalamus (RT, n=55). Two-group or four-group comparisons were made on demographic variables, BPs, and outcomes. Patients with left-sided hemorrhages presented with significantly worse neurologic scores in both hemorrhage categories and tended to sustain larger hematomas than their right-sided counterparts. Significant differences in SBPs between LP and RP (205 ± 31 vs. 189 ± 29 mmHg, P<0.01) as well as in diastolic BPs between LT and RT (109 ± 19 vs. 97 ± 20 mmHg, P=0.03) were noted. Multivariate regression analysis showed that patients with SBPs of at least 220 mmHg were 2.9 times more likely to harbor left-sided hemorrhages. There were no significant intergroup differences in responsiveness to a continuous intravenous nicardipine infusion or 30-day mortality rates. Although the differences in BPs are unlikely to have influenced outcomes, future trials involving supratentorial hypertensive intracerebral hemorrhages may benefit from considering hemispheric differences in BP and other demographic variables.