Primary liver cancer is a malignant tumor caused by abnormal cellular proliferation and differentiation of the hepatic cells or bile duct cells. The formation of tumor thrombus is one of the most important factors for the poor prognosis of primary liver cancer, so a better understanding of tumor thrombus (including portal vein tumor thrombus and bile duct tumor thrombus) has great importance for clinical management and estimation of prognosis. This paper addresses the research progress in the study of primary liver cancer complicated with tumor thrombus.