Mesalazine is a 5-aminosalicylic acid (5-ASA) used to induce and maintain remission in inflammatory bowel disease (IBD). It is metabolised to its active form by the intestinal mucosa, thus more useful in treating ulcerative colitis (UC) than transmural Crohn disease (CD). There is little published evidence that mesalazine is effective in maintaining remission in paediatric CD. A retrospective study was done in 19 children diagnosed with CD and prescribed mesalazine monotherapy after successful induction therapy in our centre. Four children had ileal disease, 9ileocolonic disease and 6 had colonic disease only. Out of the total of 19 children, the number of children in remission on mesalazine alone was 18, 14 and 5 at 3, 6 and 12 months respectively. The commonest reason to start additional therapy was on-going disease activity. Adverse effects were rare, leading to cessation of the drug in only one child. This study shows that a proportion of CD patients will enter a significant period of remission while taking mesalazine as sole maintenance drug. The beneficial effect of mesalazine in CD does not appear to be restricted to those with disease limited to the colon. Our results suggest a role for mesalazine in paediatric CD.