Abstract: Immune checkpoint inhibitors (ICIs), as one of relatively advanced antitumor treatment methods in recent years, have achieved significant therapeutic effects in the treatment of multiple systemic tumors. However, their application in gastrointestinal tumors is not satisfactory, with treatment bottlenecks. This article summarizes the challenges and possible solutions faced by ICIs in the treatment of gastrointestinal tumors to help clinicians better understand the limitations and future development directions of ICIs and thus develop more effective treatment strategies.