This study tried to approximate the mechanisms of ocular changes in Crohn's disease and ulcerative colitis. First, we reported a series of three patients with ocular complications and chronic inflammatory bowel disease. In all cases, we reported the association of ocular disorders with: various infections: intestinal, extra-intestinal complications, immunological troubles, genetic background: HLA B 27. Second, we reviewed the literature concerning ocular changes in ulcerative colitis and Crohn's disease. Recent immunological developments are studied, regarding: genetic aspects, allergic manifestations. immune complexes and role of IgA antibodies. Practically, uveitis, retinal inflammation or vasculitis can be associated with Crohn's disease and ulcerative colitis. Immunological studies of these patients will allow a better understanding of the mechanisms of the ocular lesions, which remain is complex, multiple and non specific.