Psychological stress has long been reported to be linked with the disease activity of patients with inflammatory bowel disease (IBD). However, the mechanisms of psychological stress involved in pathogenesis of IBD are still to be elucidated. We have previously shown that catecholamine participates in progression of acute colitis through a2-adrenoreceptors. The study aimed to explore the pivotal role of catecholamine in psychological stress-induced colitis. The expression of dopamine β-hydroxylase (DBH), the rate-limiting enzyme in regulation of catecholamine synthesis, was induced in colon tissues of mice with restraint stress, indicating the association of catecholamine synthesis with psychological stress. Notably, pretreatment with RX821002, an a2-adrenoceptor antagonist, attenuated inflammatory responses of psychological stress-induced colitis. Intriguingly, DBH levels were elevated in colon tissues of patients with active IBD. The study suggests that a2-adrenoreceptors/catecholamine play pivotal role in psychological stress-induced colitis and might contribute to the development of human IBD.