Abstract: Bile duct tumor thrombus(BDTT) is a special type of hepatocellular carcinoma(HCC). The incidence of BDTT is 0.5%-2.5% of all HCC patients. BDTT progresses rapidly and has a very poor prognosis. Now there is no consensus of diagnosis and treatment of BDTT, resulting in the nonstandard treatment of BDTT. Based on the evidence-based medical evidence obtained from the international studies on BDTT in recent years, as well as the clinical practice in our country, the Chinese Association of Liver Cancer of Chinese Medical Doctor Association formulates the "Chinese expert consensus on multidisciplinary diagnosis and treatment of hepatocellular carcinoma with bile duct tumor thrombus (2020)", which has systematically addressed the clinical manifestations, diagnostic methods, staging, surgical and adjuvant treatment, and other local, regional and systemic treatments of HCC with BDTT. This consensus is designed to standardize and popularize the diagnosis and multidisciplinary treatment of BDTT to improve overall prognosis of the disease.