We report a case of pancreatitis as the first symptom of cystic fibrosis in a 22-year-old woman. The diagnosis was suspected upon the history of nasal polyposis and severe episodes of respiratory infections in infancy. The diagnosis was confirmed by sweat test. Genotyping showed a compound heterozygosity for mutations delta F508 and 5T. Acute pancreatitis is a rare manifestation of cystic fibrosis and an exceptional mode of initial presentation of the disease. It occurs in pancreatic sufficient patients, especially in young adults. This exceptional case shows that cystic fibrosis should be suspected in each case of idiopathic pancreatitis. Indications of cholecystectomy in patients with associated gallbladder lithiasis is discussed.