Immunotherapy is an important treatment method in tumor therapy. Among them, programmed death-1/programmed death ligand-1 inhibitors are the immune preparations with mature application and great survival benefit at present. Programmed death-1/programmed death ligand-1 inhibitors brought better clinical benefits to patients with esophageal cancer and provided more favorable choice for the treatment of esophageal cancer. This article introduces the mechanism of action, application in esophageal cancer, and efficacy predictors of programmed death protein-1/programmed death protein ligand-1 inhibitors, aiming to provide a theoretical basis for the more rational use of programmed death protein-1/programmed death protein ligand-1 inhibitors in patients with esophageal cancer.