Currently there are no data available regarding the incidence of true ulnar artery aneurysms of the hand. The occurrence of this phenomenon is presumed to be exceedingly uncommon. Based on an online literature search, we report a novel case of a true ulnar artery aneurysm in a young boy. Our experience involved an 8-year-old with an asymptomatic, rapidly expanding, non-pulsatile, true ulnar artery aneurysm located on the inner aspect of the hypothenar eminence. Clinical assessment eliminated etiological relationship with the hypothenar hammer syndrome. Treatment involved resection of the diseased artery along with reconstruction using an interposition, reverse saphanous vein graft.