Authors present 16 cases of posterior fossa tumors in which both vertebral angiography and computed tomography were performed and pathologic diagnosis verified at Seoul National University Hospital form January, 1978 through December, 1979. The radiographic finding are analyzed with emphasis on abnormal vascularity on angiography and computed tomographic findings. The purpose of this study is to understand the correlation between angiographic vascularityand contrast enhancement on post-contrast scan. The results are as follows : 1. The C.T.scan of all the cases show contrast enhancement , whereas only 6 cases show abnomal vascularity on angiogrpahy. 2. Angiographic abnormal vasculatures influence onstrong contrast enhancement on C.T. but the converse is not necessarily true. 3. The vertebral angiography appears to be of less diagnostic value for cases with slight contrast enhancement on C.T. than for cases with strong enhancement on C.T.