Barrett's oesophagus in young individuals is a rare pathology. The purpose of this study was to identify those risk factors involved in Barrett's oesophagus (BO) development in children. We performed a case-control study between years 2000 and 2010. Cases had endoscopic BO with histological confirmation of gastric or intestinal metaplasia. For each case, three to four controls were selected from our ph-monitoring database. They were matched by age, + 2 years, or by associated features (oesophageal atresia or Down's syndrome) when appropriate. An analysis of the demographic variables, symptoms and endoscopic data was performed: sex, digestive or respiratory symptoms, exposition time to gastroesophageal reflux (GER) without treatment with proton-pump inhibitors (PPI) and Helicobacter pylori (HP) presence. Six patients were diagnosed with BO (age range: 8 months-14 years) and a 21 control samples were included. Both groups were comparable in sex and age parameters. There were no differences in clinical presentation, neither in presence of hiatal hernia nor HP colonisation. The ph-monitoring register did not differ between groups, median Reflux Index or Boix Ochoa Index. The only risk factor found in this study is the exposition time to GER: OR = 1.046; CI95% (1.007-1.086); p = 0.021. Our results suggest that exposition time to GER without treatment with PPI is related to Barrett's oesophagus development in childhood.