Introduction– Primary intraventricular haemorrhage (PIVH) is an uncommon type of intracerebral haemorrhage. Relatively little is known about clinical and imaging features, and even less about prognosis and predictors of mortality. Material and methods– We analysed clinical and imaging features, causative factors and outcome of 26 patients with CT brain scan evidence of PIVH. A multivariate regression model of failure time data was used to assess predictors of in-hospital mortality. Results– Loss of consciousness was the first manifestation of PIVH in six patients and occurred after all other symptoms in five. In other patients, onset was characterized by headache, vomiting, confusion and disorientation (n=8) or by headache with or without vomiting (n=7). Angiography revealed vascular malformations in eight patients (31%). Other possible causative factors were clotting disorder in one patient and arterial hypertension in 10. No cause was identified in seven patients. Early hydrocephalus was the most frequent complication and resolved spontaneously in a minority of patients. In-hospital mortality was high (42%): four patients died early of direct consequence of bleeding and seven died after clinical worsening because of increasing hydrocephalus or other adverse events. Multivariate analysis indicated Glasgow Coma Scale ≤ 8 (OR 4.67; 95% CI 1.22–17.92) and early hydrocephalus (OR 4.93; 95% CI 1.13–21.59) as independent predictors of in-hospital mortality. Conclusion– In patients with PIVH, hydrocephalus seems to be a critical determinant of in-hospital mortality and this suggests the need for early treatment strategies.