Liver stem cells are primitive cells with self-renewing capacity and bidirectional differentiation potential to differentiate into mature hepatocytes or biliary epithelial cells. Liver stem cells not only play roles in the homeostasis maintenance, injury repair and regeneration of liver, but also have huge potential applications in cell therapy of liver diseases, construction of bioartificial liver and liver-oriented gene therapy. In this review, we summarized the major types of liver stem cells, as well as their origins and molecular markers.