We used recently developed biopsy forceps to acquire transpapillary tissue in a consecutive series of 43 patients with pancreaticobiliary ductal strictures found during endoscopic retrograde cholangiopancreatographic examinations. There were 19 cholangiocarcinomas, 15 pancreatic carcinomas, five benign biliary, and four benign pancreatic ductal strictures. Tissue sampling from the strictures was successful in 41 patients (95.3%), without complications. All specimens were adequate for histologic evaluation. Eighty-one percent of the patients with carcinomas were diagnosed histologically by this technique. Sensitivity was 88% for cholangiocarcinoma and 71% for pancreatic carcinoma. There were no false-positive results. We conclude that transpapillary biopsy, being a simple, safe, and convenient method, should be applied as an initial diagnostic means during endoscopic retrograde cholangiopancreatography.