PURPOSE: To determine clinical outcome in cases of traumatic intraventricular hemorrhage(TIVH) according to the mechanisms and amount of hemorrhage seen on initial CT. MATERIALS AND METHODS: We retrospectively reviewed the initial CT findings of 61 patients with TIVH. The mechanisms of TIVH were analyzed on the basis of the following CT findings: Type I; large intracerebral hematoma extending to adjacent ventricle; Type II: hemorrhagic and/or non-hemorrhagic diffuse axonal injury in the thalamus and basal ganglia; Type III: multiple small hemorrhagic lesions in the septum pellucidum, fornix, corpus callosum, and periventricular region, which may be due to inner cerebral trauma, Type IV: evidence of hypoxic brain injury, and Type V: TIVH with contusion and small subdural or epidural hematomas. The amount of TIVH was classified according to the Graeb score. We analyzed these mechanisms on the basis of CT findings, and for prognosis, correlated these with clinical outcomes and the Glasgow coma score. RESULTS: Prognosis was good in types V and III and poor in type I and II(p=0.001). In patients with a Graeb score of 4 or less, the clinical outcome was better than in those with a Graeb score above 5(p=0.03). Patients with a lower initial Glasgow coma score had poor outcomes(p=0.001). CONCLUSION: The hemorrhage mechanism in patients with TIVH could be important for estimating clinical outcome, especially during the early phase. In patients with type V or III TIVH, clinical outcome was better than in those with type I or II.