Penile induration, a disease of connective tissue, requires the precise delineation and differentiation of inflammatory changes (plaques) for accurate therapy. Seventy two patients with clinically suspected Induratio penis plastica (IPP) underwent ultrasound examination between 1984 and 1991. In 37 patients (aged 18 to 80) the diagnosis was proven by ultrasound. Out of this group 27 patients were examined with magnetic resonance imaging (MRI), 15 of them with additional intravenous application of adolinium DTPA (Gd-DTPA). All examinations were performed within four weeks. The results showed, that ultrasound was able to detect plaques and changes of the tunica albuginea in all 37 cases, but MRI was more sensitive in the detection of possible inflammatory change (T2-prolongation and moderate Gd-DTPA enhancement in gradient-echo sequences.