Inflammatory bowel diseases are chronic, non-infectious intestinal inflammation of unknown origin that afflicts individuals of both sexes throughout life. The disease is clinically characterized by two overlapping phenotypes- ulcerative colitis and Crohnś disease . Ulcerative colitis and Crohn’s disease predominantly affect colon Crohn’s disease the distal small intestine (terminal ileum). Histologically like as a superficial (UC) or transmural (CD) inflammation. Clinical and laboratory studies in human with IBD have long suggested that genetic and environmental factors play an important role in the pathogenesis of these disorders. Experimental animal models allow study of possible etiologic agens, interactions among different components and identification of immunologic processes and genetic susceptibility in ways that are not possible in humans. There is no right or wrong model of IBD, the purpose of this review is to define what the different models have told us and where they seem to be most useful for the study of IBD.

        Key words: Crohn’s disease – ulcerative colitis – experimental animal models