Abstract: Gastric cancer is one of the most common malignant tumors with high morbidity and mortality in our country. By the time of their initial diagnosis, most gastric cancers progress to the advanced stage, and consequently, have poor prognoses. Moreover, the treatment status is not optimistic. Immune escape is a major mechanism of tumorigenesis and tumor development. Programmed death-1 (PD-1) and programmed death-ligand 1 (PD-L1) are substantial for facilitating immune escape, and their combination is an important pathogenesis mechanism in tumor cell immune escape. Thus, one method to kill tumor cells is by blocking this combination. Many clinical trials have demonstrated that PD-1/PD-L1 inhibitors can significantly improve the prognosis of patient with advanced gastric cancer. Furthermore, the treatment efficacy can be improved by combining PD-1/PD-L1 inhibitors with chemotherapy, targeted therapy, and radiotherapy. This article reviews the research progress on PD-1/PD-L1 inhibitor combination therapy for advanced gastric cancer.