We describe a patient presenting with palpable lymph nodes due to non-Hodgkin's lymphoma. Chemotherapy induced complete remission. One year later he complained of cramping abdominal pain, diarrhoea and bloody stools all due to Crohn's disease of the colon. There are only a few more patients described with a combination of inflammatory bowel disease and malignant lymphoma. So far there is no explanation for the co-incidence of the two diseases.