Pancreatic ductal adenocarcinoma(PDAC)is one of the most aggressive solid tumors with poor prognosis,owing to the difficulty of early diagnosis and the lack of therapeutic regimens.Extensive fibrosis is a typical histopathological feature of pancreatic cancer,in which cancer-associated fibroblasts(CAF)play a crucial role.CAF,the predominant cell type in the tumor microenvironment(TME),has multiple cellular origins and highly plasticity.CAF have been shown to crosstalk with pancreatic tumor cells and other cells in TME,which participate in all stages of tumor progression and contributes to tumorigenesis,metastasis and drug resistance.This work not only focuses on the origin and phenotypic heterogeneity,but also on the function and underlying mechanism of CAF in pancreatic TME.In-depth understanding the role and function of CAF will provide theoretical basis and possibilities for the clinical therapies of PDAC.