Crohn's disease (CD) is a chronic non-specific intestinal inflammatory disease with incompletely clarified etiology, which can involve multiple organs and systems , and is prone to severe complications such as intestinal obstruction, perforation, and fistula.Currently, the main therapeutic drugs for CD include aminosalicylates, glucocorticoids, immunosuppressants, biological agents, etc. With the development of medical technology, biological agents have begun to be applied to moderate-to-severe Crohn's disease, providing new treatment options for patients with moderate-to-severe Crohn's disease. Guselkumab is a selective inhibitor of the interleukin-23 (IL-23) p19 subunit.The GALAXI2 and GALAXI3 studies demonstrated that guselkumab can better achieve the therapeutic goal of mucosal healing. The clinical remission rates of guselkumab at week 12 were 47.1% and 47.1%, respectively, and the endoscopic response rates were 37.7% and 36.2%, respectively . Intestinal ultrasound lUsnoninvasive, reproducible, convenient, and inexpensive test that can greatly increase the frequency of assessing treatment response and speed up the clinical decision-making process.The 2019 ECCO-ESGAR guidelines recommend intestinalultrasound for disease monitoring in patients with CD. There are no validated indicators to predict the efficacy of guselkumab treatment in patients with moderate-to-severe CD in the currently available studies. Currently, there are no national orinternational studies in which intestinal ultrasound predicts the efficacy of guselkumab therapy. Therefore, we propose for the first time that intestinal ultrasound be used as a method to predict the response to guselkumab in CD patients, with the aiproviding evidence to guide the development of individualized treatment plans.