Authors present 16 cases of posterior fossa tumors in which both vertebral angiography and CT were performedand pathologic diagnosis verified at Seoul National University Hospital from Jan. 1978 through Dec. 1979. Theradiographic findings are analyzed with emphasis on abnormal vascularity on angiography and computed tomographicfindings. The purpose of this study is to understand the correlation between angiographic vascularity and contratenhancement on post-contast scan. The results are as follows; 1. The CT scan of all the cases show contrastenhancement, whereas only 6 cases show abnormal vascularity on angiography. 2. Angiographic abnormal vasculaturesinfluence on strong contrast enhancement on CT but the converse is not necessarily true. 3. The vertebralangiography appears to be of less diagnostic value for cases wtih slight contrast enhancement on CT than for caseswith strong enhancement on CT.