Sixteen cases of pituitary adenomas, which have been confirmed by operation or open biopsy, wee reviewed and analized on clinical symptoms, radiologic findings and related references. These cases were among 36 cases diagnosed at Severance Hospital, Yonsei University College of Medicine. The summary was as follows; 1. Among 16 cases chromophobe adenoma are 12 cases, eosinophilic one is 1 case and unknown cell type cystic ones are 3 cases, histologically. 2. Most frequent chief complaints are insidious onset visual impairment, headache and loss of libido and/or amenorrhea in decreasing order. 3. The plain skulls reveal typical ballooning and cup shape enlargement of sella, among them, there are marked destroyed sella changes in 3 cases. Double contour of sella are present in 3 cases. There is no definite calcification, osteoblastic change around sella neither typical acromegalic skull. 4. The carotid angiograms, which was performed in 14 cases, show typical lateral displacement f intracavernous, and supraclinoid portion of internal carotid artery and opening of carotid siphon in 10 cases. And elevation of proximal portion of anterior and middle cerebral artery are evident. There is no evidence of tumor brush. 5. The fractional pneumoencephalograms of 9 cases show the large tumor mass in chiasmatic cistern in all cases. These conventional studies could be helpful in the diagnosis of sella tumor, especially pituitary adenoma, however, authors are recommended for further radiologic study such as autotomogram during pneumoencephalogram or cavernous sinus angiogram for better differential dianosis.