There is a widespread impression that stressful life situations influence the clinical course of a wide variety of gastrointestinal disorders, including inflammatory bowel disease. However, demonstrating a causal relationship is complex and the results obtained in clinical studies are contradictory. In the last few years, the use of experimental stress models in laboratory animals have provided solid evidence of the physiopathological effects of stress on the digestive tract as well as of the cellular and molecular mechanisms underlying the association between physical and/or psychological stress and gastrointestinal disorders. In inflammatory bowel disease, the marked intestinal barrier dysfunction, which is mainly related to the stress-induced increase in paracellular epithelial permeability, could be partially responsible for the reactivation and increase in the severity of inflammatory bowel disease observed in various experimental stress models.