Aneurysms arising from the posterior circulation are 5-19% of total intracranial aneurysms. Althought many neurosurgeons have challended with various innovations but the confinned surgical space, complicated anatomical structure and many small perforators to vital organ of brain were remained the barrier that we we have to overcome. From July 1987 to December 1994, we have been operated on 23 cases of posterior circuation aneurysms among 409 cases of surgically treated all intracranial aneurysms. The present 5.6% of all intracranial aneurysms, the average age of these patients was 49 years old. The ratio of male to female was 1 : 1.8. The number of basilar bifurcation artery aneurysms(BBAA) were 14(61%), the posterior cerebral artery(PCA) aneurysms 3(13%), the upper basilar trunk aneurysm 1, posterior inferior cerebellar artery(PICA) aneurysm 3(13%), anterior inferior cerebellar artery(AICA) aneurysm 1 and vertebral artery aneurysm 1. Five patients had accompanined with anterior circulation aneurysm and one patient had concomitant arteriovenous malformation. We have successfully clipped 12 cases and wrapped 2 cases of BBAA aneurysms through modified pterional approach and subtemporal approach according to the hight of basilar bifurcation and the other posterior circulation aneurysms are all clipped through most available approaches including lateral, far-lateral suboccipital and interhemispheric approach. Surgical outcome was good in 15 cases, fair in 4 cases, poor in 3 cases and one patient expired.