Abstract: Pancreatic cancer is one of the most common tumors in digestive system, which is characterized by insidious clinical symptoms, strong invasion, easy metastasis and high mortality. In recent years, immunotherapy is a new direction to the treatment of solid tumors, but its applica-tion in pancreatic cancer is limited by tumor microenvironment of pancreatic cancer. The authors systematically analyze the tumor microenvironment of pancreatic cancer, summarize the clinical researches related to pancreatic cancer immunotherapy, and discuss the prospect of pancreatic cancer immunotherapy.