Provided is a method of stably maintaining and culturing "hepatoblast-like cells" generated during a differentiation-inducing process from pluripotent stem cells to hepatocytes. The present invention also provides a culture product obtained by the culture method. The hepatoblast-like cells can be maintained and cultured stably by bringing a laminin into contact with the hepatoblast-like cells. The method of the present invention which uses a laminin makes it possible for the first time to culture, maintain, and proliferate the hepatoblast-like cells. Desired mature cells such as mature hepatocytes and bile duct epithelial cells can be generated in a short time period and can be acquired at a desired timing by maintaining the hepatoblast-like cells. Further, the resulting cultured hepatoblast-like cells were demonstrated to be capable of being induced to differentiate into mature hepatocytes, mature cholangiocytes, bile duct epithelial cells, and the like. Thus, a substantially pure culture product of the present invention can be utilized as a composition for transplantation for use in regeneration of hepatocytes and/or bile duct epithelial cells.