Three patients with juvenile papillomatosis of the breast are described. The lesions were apparent clinically as a palpable mass. At mammography, juvenile papillomatosis was not depicted in two patients and was seen as a poorly defined mass in one case. In all patients, high-frequency ultrasound examination showed an ill-defined, inhomogeneous mass with one or several small (up to 0.4 cm), rounded, relatively echo-free areas, which were seen mainly or exclusively near the borders of the lesion.