The authors describe a case of aneurysm of the popliteal artery which developed in the vicinity of a solitary bony exostosis. In a review of the literature they found 33 other cases, in the majority of which the aneurysm was a false aneurysm. Diagnosis was made by arteriography. The results of treatment were good unless complications such as thrombosis or emboli were already present. In the authors' case, resection of the exostosis and arterial grafts were performed with a good end result.