A genesis of the gallbladders is an uncommon finding in biliary surgery. Its incidence varies from 0,03 per cent to 0,09 per cent in autopsies series. The authors report a case in which the agenesis of the gallbladder was found during the operation in a patient without choledocholithiasis. A parcial review of the literature was done with special reference to the difficulties in establishing the diagnosis preoperativelly