Abstract: Pancreatic ductal adenocarcinoma (PDAC) is the main subtype of pancreatic cancer and is characterized by strong invasion, treatment resistance, and poor prognosis. Early diagnosis and intervention are particularly important for patients with PDAC; however, still no effective means for the diagnosis and treatment of this disease in clinical practice exists. In recent years, extracellular vesicles have become a research hotspot for the early diagnosis and targeted therapy of PDAC because of their ability to carry tumor-specific molecules. Extracellular vesicles can not only participate in pathological processes, such as the occurrence and metastasis of PDAC, but also in the regulation of drug resistance during treatment. Therefore, extracellular vesicles have been shown to have a great clinical potential as liquid biopsy markers and drug delivery carriers for the diagnosis and treatment of PDAC. This article has systematically reviewed the research progress in the diagnosis and treatment of extracellular vesicles in PDAC, in order to provide new ideas and references for the diagnosis and treatment of PDAC.