Abstract:As an emerging targeted biologic agent in recent years，ustekinumab （UST） can specifically bind to interleukin（IL）-12 and IL-23，block the activation of downstream proinflammatory factors，and achieve a broad inhibitory effect on systemic inflammatory responses. Its efficacy and safety have been confirmed in psoriasis and Crohn's disease（CD）. As another type of inflammatory bowel disease（IBD），ulcerative colitis（UC）has high disability and mortality rates. Foreign experts recommend UST as a first-line treatment for moderate-to-severe UC，but clinical data on UST for treating moderate -to-severe UC remain limited in China. This article systematically reviews clinical studies ofUST in UC，and summarizes its mechanism of action，clinical efficacy，safety，and response predictors. UST demonstrates rapid response，favorable efficacy，and high safety，which may provide a reference for individualized treatment of moderate-to-severe UC and theoretical guidance for the development of research related to UST treatment of moderate-to-severe UC.