It seems to be well established that the direct surgical treatment of intracranial aneurysm such as clipping, trapping and wrapping the aneurysm. These operations have brought about excellent results but are not perfect because recurrent aneurysm and rebleeding of aneurysm have been reported shortly after the operation. However, it is very rare that subarachnoid hemorrhage arising from recurrent aneurysm long time after the operation, authors have experienced 3 cases of recurrent aneurysm in the same region long after the surgery. Two cases were readmitted to our hospital following repeat episode of subarachnoid hemorrhage. Carotid angiogram showed a new small aneurysm locating about the same place where previously operated aneurysm was situated. One of them showed development of new aneurysm at the anterior communicating after 4 years artery the neck clipping, the other one was recurrent aneurysm 9 years after the neck clipping of aneurysm at the anterior communicating artery. Two cases were treated by reclipping and got well. It has been reported in the articles that 20 cases of recurrent aneurysm were located about the same place where previously clipping aneurysm was performed. Causes of such recurrence of already clipped aneurysm could be divided into two groups. First group was considered that the treatment was unsatisfactory, because the clip had been improperly placed. The other group was considered as mechanical failure of aneurysmal clip that resulted in "slipped out," or "broken clip", and local fragility of the arterial wall adjacent to clip edge. Last case had a giant pseudoaneurysm.(ABSTRACT TRUNCATED AT 250 WORDS)