Authors report the case of a young man affected by an aneurysm at the humeral artery. The relevance of this case was due to its notable rare incidence at such level as well as its difficult etiologic diagnosis. Patient was treated by an aneurysmectomy and a basilic vein ipsilateral was interposed. Immediate and after 18 months results were satisfactory. Arteriographic and anatomopathologic studies are presented.