Digestive disturbances are frequent in adults with cystic fibrosis. They can lead to malnutrition which in turn is deleterious to the prognosis. We summarise the information on epidemiology, pathogenicity, signs, diagnostic criteria and treatments of exocrine pancreatic insufficiency, gastro-oesophageal reflux and denutrition (which are all frequent) but also of constipation, rectal prolapse, distal intestinal obstruction syndrome, and liver diseases. The main recommendations are the following: 1--know how to treat pancreatic insufficiency with enzyme replacement and vitamins; 2--know how to treat aggressively any gastro-esophageal reflux; 3--diagnose and treat denutrition as early as possible; 4--know the distal intestinal obstruction syndrome to avoid abusive and dangerous surgery; 5--know that the most severe hepatic diseases can be treated by liver transplantation.