Pancreatic stellate cells (PSC) is the most vital element in the stroma of pancreatic ductal adenocarcinoma (PDAC), which plays an irreplaceable role in the development of pancreatic carcinoma. Recent researches concentrate on the interaction between PSC and pancreatic cancer cells (PCC) and the function of PSC in PDAC microenvironment. PSC could be stimulated to activate in some conditions, such as alcohol, oxidative stress and hyperglycemia, etc. PSC activation could be occurred at the early stage of PDAC and would generate collagen to form tumor associated microenvironment, which would accelerate the proliferation of tumor cells and defended the cytotoxicity of chemotherapeutic drugs. Besides, PSC can also interact with other stroma compositions such as endothelial cells and immune cells to form the tumor stroma (e.g., angiogenesis, immune escape and neural invasion), which assists the invasion of cancer cells. Above all, it is pivotal to clarify the interplay between PSC and PDAC as well as stroma ingredients.