There is currently no strong prognostic factor in pancreatic cancer. K-ras is the most commonly mutated gene in pancreatic cancer, with a mutation rate of 75% to 95%. These high mutation rates are expected to be useful for diagnosis and prognostic factors in future. Currently, K-ras mutation tests are often performed in tissues, and there are various limitations, in particular, limited obtaining of sufficient tissues. In this regard, analyzing the prognosis of pancreatic cancer through non-invasive blood testing has significant advantages. And Prognosis analysis through blood tests can be done through blood circulating tumor DNA. The relationship between prognosis and blood circulating tumor DNA has already been studied in other cancers such as colorectal cancer, and there have been several studies in pancreatic cancer. However, there are not many research results yet, and there are cases in which the results differ from study to study. Therefore, in this study, we aimed to compare the overall survival of patients with pancreatic cancer diagnosed by EUS-FNA according to the presence and amount of blood circulating tumor DNA with K-ras mutation.