Among 202 aneurysmal patients with SAH who were admitted to Kyungpook National University Hospital from Jan. 1984 through Jan. 1988, the incidence of ventricular dilatation confirmed by postoperative follow-up brain CT scannings was 32.2%(65 cases). And 33 cases(19.3%) was in mild ventricular dilatation, 9 cases(4.5%) was in moderate and 23 cases(11.4%) in severe who needed the shunting procedure were analysed. The incidence of ventricular dilatation to the site of aneurysm was highest in A-com A. aneurysm(42.2%), followed by P-com A. aneurysm(36.4%) and MCA aneurysm(11.3%). The incidence of ventricular dilatation and the need for shunting was higher in multiple bleeding patients than the single. The good risk patients had meaningfully lower incidence of ventricular dilatation than the poor risk group. In the delayed surgical group showed significantly more numbers of ventricular dilatation needing the shunt than the cases in early group.