Objective To explore the factors related to hematoma enlargement in the early stage of supratentorial hypertensive intracerebral hemorrhage (SHICH) and its prognosis.Methods A retrospective analysis was conducted on the clinical data of patients who were diagnosed with SHICH in the Neurosurgery Department of the Affiliated Hospital of Xuzhou Medical University from January 2015 to May 2019 and received conservative treatment on admission. Among the patients, 346 met the diagnostic criteria established at the Fourth National Conference on Cerebrovascular Diseases in China and had complete clinical data. According to the inclusion and exclusion criteria, the patients were divided into hematoma enlarged group (HE group, 101 cases) and hematoma unenlarged group (HUE group, 245 cases). The patients were analyzed for relevant indices such as sex, age, blood type, diabetes history, hematoma location, hematoma morphology, hematoma volume, Glasgow Coma Scale (GCS) on admission, time to disease onset since initial head CT examination, and red cell distribution width, hemoglobin, platelet, white blood cell count, absolute neutrophil count, absolute lymphocyte count, alanine aminotransferase, aspartate aminotransferase, albumin, creatinine, blood glucose (GLU), serum calcium, serum magnesium, total cholesterol, triglyceride, low-density lipoprotein (LDL), high-density lipoprotein, coagulation function (PT, APTT, and FIB), and blood pressures (SBP and DBP) on admission. The prognoses of the patients were evaluated according to the Glasgow Outcome Scale at 6 months after disease onset.Results An univariate analysis showed that there were significant differences between the two groups in sex, blood type, hematoma morphology, hematoma volume, time to disease onset since initial head CT examination, GCS on admission, GLU, and LDL (P<0.05); differences in these indices (except hematoma volume) between the two groups were also significant in a further multivariate logistic regression analysis (P<0.05). The results of the prognostic analysis showed that the mortality and disability rates of patients in the HE group were significantly higher than those in the HUE group.Conclusions Sex, blood type, hematoma morphology, time to disease onset since initial head CT examination, GCS on admission, GLU, and LDL are independent factors influencing hematoma enlargement in the early stage of SHICH. Patients with the hematoma enlargement have worse prognoses.