The authors studied thirty one cases (18 women, 13 men) of extracorporeal shock-waves lithotripsy on symptomatic gallbladder stones realized with piezoelectric generators. There were one to six stones per patient with individual stone size from 8 to 40 mm; among them 16% were calcified. Any anesthesia was necessary. Shock-wave frequency was 1.25 and 2.5 Hz. The average number of shock waves administered was 4,600 per treatment. Fragmentation occurred in 67% after first treatment and in 74% after second treatment. Gallstones disappeared in 9.5% and 19.5% of patients after 6 weeks and 4 months respectively. There was no modification after four treatments in 22.5% of patients. Minor side effects were noted: back pain (29%) probably because of uncomfortable position during treatment; increased thickness of gallbladder wall (26%); biliary pain (22%). Two episodes of biliary tract obstruction by stone fragments (one mild pancreatitis, one jaundice with liver enzymes elevation) disappeared spontaneously. These results were comparable with those of other groups using the same shock waves lithotripter.