According to the statistics of the National Cancer Center, there were nearly half a million deaths from upper gastrointestinal tumors in China in 2022, which seriously threatens the health and safety of the people. Photody- namic therapy for upper gastrointestinal tumors is the targeted treatment of lesions by introducing the therapeutic laser beam into the body through endoscopy and conduction fiber, which has become a medical method with the best effect and the least side effects in clinical treatment of tumors in recent years. One of the key factors affecting the efficacy of photodynamic therapy is the type and dose of photosensitizer. This paper studies the development of photosensitizers, their current application status and therapeutic effects in the treatment of upper gastrointestinal tumors. It compares the research progress at home and abroad, analyzes the characteristics and requirements of photosensitizers in photodynam- ic therapy, and discusses the future research directions.