Objective To study the relationship between the systemic immune-inflammation(SII)index and the prognosis of intracerebral hemorrhage(ICH)in the acute phase.Methods We retrospectively collected the clinical data of patients with supratentorial ICH admitted to the Department of Neurology of Chifeng Clinical Medical College of Inner Mongolia Medical University from January 2021 to January 2022.The patients were grouped according to their outcomes(a modified Rankin Scale score of 3-6 points was considered as a poor prognosis)and SII index quartiles.The baseline data and SII index of patients with different prognoses were compared.The relationship between the SII index and the Na-tional Institutes of Health Stroke Scale(NIHSS)score and hemorrhage volume was analyzed.Results Compared with pa-tients with a good prognosis,those with a poor prognosis had a significantly greater SII index,a significantly larger hemor-rhage volume,a significantly higher proportion of intraventricular extension,and significantly higher leukocyte and neutro-phil counts(all P<0.001).Patients with the SII index≥1.58 had a significantly higher NIHSS score and a significantly larger hemorrhage volume than patients with the SII index≤0.53(both P<0.001).Conclusion The SII index is related to the acute prognosis of patients with supratentorial ICH,suggesting that regulating neuroinflammatory response may im-prove the prognosis of patients with ICH.