Provided in the present invention is a method for inducing pluripotent stem cells to differentiate into ventricular myo-cytes in vitro, which is achieved by maintaining, amplifying and culturing pluripotent stem cells in vitro, adding a substance capable of activating the Smadl/5/8 signaling pathway directly or indirectly into the culture medium when pluripotent stem cells are in the middle stage of myocardial differentiation, i.e. the period of differentiating into cardiac muscle cells from mesoderm cells or myocardial precursor cells, which enables stem cells to differentiate into ventricular myocytes directionally. Ventricular myocytes with biological activity and function are obtained successfully by means of the method of the present invention, which reveals the regulatory mechanism during differentiation of myocardial precursor cells into ventricular myocytes moreover, the human ventricular myo-cytes obtained via differentiation can be widely used in treating myocardial infarction by cell transplantation, in toxicological analys - is of the heart and in the development of heart-related drugs.
