4HSiC semiconductor is an ideal electronic material for high temperature, high frequency, and high power electronic devices. In recent 20 years, the material growth technology has been developed, and the quality of 4HSiC materials has been gradually improved. In this paper, the necessity of homoepitaxial growth of 4HSiC is briefly described. Then, several important aspects of the material science of 4HSiC, such as impurity doping, extended and point defects, and highspeed growth process are reviewed. At last, the current status of domestic 4HSiC epitaxy industrialization is introduced.