Abstract: Pancreatic cancer is the most common pancreatic tumor, with a 5-year survival rate of less than 5%. Therefore, early detection, effective evaluation and appropriate treatment are critical to the disease. Since diffusion weighted imaging (DWI) was first reported in 1984, it has become more and more important in clinical research and applications. As part of the sequence of magnetic resonance imaging, DWI provides important information for the diagnosis and differential diagnosis of pancreatic cancer, as well as for the evaluation of therapeutic effects. This article reviews the technology of DWI and its application in the diagnosis of pancreatic cancer.