Coeliac disease and Crohn's disease are among the most well known gastrointestinal disorders, with distinct pathogenic mechanisms. However, because of some overlapping features between these two conditions, there may be some inevitable misdiagnoses. In addition, diarrhoea and changes in bowel habit may lead the physician to misdiagnose more common disorders such as irritable bowel syndrome. There are a few cases reporting both coeliac and Crohn's disease in the same patient. Here we report a case of a 32-year-old woman suffering from long term diarrhoea who was eventually discovered to have coeliac disease and Crohn's disease simultaneously.