The aim of the study was to check the efficiency of shock waves in the treatment of Peyronie's disease. The instrument, because of its lithotriptic power, already used in the treatment of orthopedic disease and salivary stones, can be used to break plaques in induratio penis plastica. A total of 481 patients affected with Peyronie's disease were entered into a prospective trial. Patients with big plaques or with an initial stage of degeneration were excluded. We divided the patients into three treatment groups: a) shock waves alone in 56 patients; b) a combination of shock waves and calcioantagonist (perilesional injection) in 324 patients; c) calcioantagonist alone in 101 patients. The group of 101 patients (group C) treated during the previous 2 years with a medical therapy based only on the injection of calcioantagonist, was used as a control group. Ultrasound evaluation of the treated plaques showed a reduction of size in 27/56 patients of the group A, in 159/324 patients of the group B and in 39/101 patients of group C. Painful erection improved in the 91.5% of group B, against the 45.7% of group C. Furthermore, we pointed out, with interviews to the patients, a considerable improvement of the pain and of the sexual performances. The therapeutic association of shock waves with calcioantagonist injections is an effective non-operative treatment for the stabilization of Peyronie's disease.