Seven cases of coincidental aneurysm with pituitary adenoma found through the review of our personal series of 95 pituitary adenomas over a period of five years are reported. The incidence of coexisting aneurysms in our series of pituitary adenomas (7.4%) was significantly higher than that in other brain tumors (1.1%) (p less than 0.001). Its clinical significance is discussed including the indications for four-vessel angiography, the surgical approaches to these pituitary adenomas, and the management of the associated aneurysms.