Thirty patients underwent a sonographic examination of the hand because of nodular masses. In 12 out of these, the surgical removal exhibited 5 benign tumors (2 giant cell tumors, 1 angioma, 1 lipoma, 1 myoma), 5 pseudo-tumors (1 granulomatous tenosynovitis, 1 nodular tendinitis, 2 sebaceous cysts, 1 synovial cyst) and 2 congenital abnormalities of the lumbrical muscles. Except the lipoma and the nodular tendinitis, all the masses were hypoechoic or anechoic. The major interest of sonography in such a disease is a precise localization of the mass and the description of its connections with the surrounding anatomical structures.