Low re-bleeding rates within the first 14 days of aneurysmal subarachnoid haemorrhage are reported in young patients. Furthermore, re-bleeding rate for giant aneurysms does not exceed 20% according to the literature. Our own clinical impression is that the re-bleeding rate seems to be much higher in giant aneurysms than reported, particularly in young patients. The aim of this study was to evaluate re-bleeding rate after subarachnoid haemorrhage following rupture of giant aneurysms in a younger population. We reviewed records of 23 patients who were treated in our institution for subarachnoid haemorrhage from giant aneurysms between 1994 and 2003. By definition, the aneurysms were larger than 25 mm in diameter. Five patients were younger than 40 years of age at the time of the aneurysmal subarachnoid haemorrhage. All younger patients (<40 years of age) showed re-bleeding after the first subarachnoid haemorrhage within the first 14 days of the initial event. In four patients (20%) older than 40 years at the time of the haemorrhage re-bleeding could be observed within the first 14 days of subarachnoid haemorrhage. We can confirm the re-bleeding rate of approximately 20% in patients suffering from subarachnoid haemorrhage (SAH) in the group of patients older than 40 years of age. However, younger patients seem to be at much higher risk of re-bleeding from giant aneurysms.