Gastric cancer (GC) is one of the most malignant human cancers with increasing incidence worldwide, ranking among the top five malignant tumors worldwide in terms of incidence and mortality. The clinical efficacy of conventional therapies is limited, and the median overall survival (mOS) for advanced-stage gastric cancer is only about 8 months. Emerging as one of breakthroughs for cancer therapy, immunotherapy has become an effective treatment modality after surgery, chemotherapy, radiotherapy, and targeted therapy. In this review, we have summarized the progresses of clinical development of immunotherapies for gastric cancer. Major advances with immune checkpoint inhibitors (ICIs) have started to change the clinical practice for gastric cancer treatment and prognosis. Additionally, combination therapies with other modalities, such as targeted therapies, are expected to push immunotherapies to front-line. In this review, the efficacy of ICIs and targeted therapy alone or combination with existing therapies gastric cancer treatment was described and the predictive value of biomarkers for immunotherapies in gastric cancer treatment is also discussed.Copyright © 2021. Published by Elsevier B.V.