Budd-Chiari syndrome (BCS) is a clinical syndrome of portal and/or inferior vena cava hypertension due to obstruction of the hepatic veins and/or inferior vena cava. Its etiology is complex and is divided into primary and secondary; the former is mostly related to congenital developmental abnormalities or thrombosis, and the latter is often caused by tumors, autoimmune diseases, or medical factors. The clinical manifestations of BCS vary according to the site and degree of obstruction and the establishment of collateral circulation and are divided into asymptomatic and symptomatic types. Imaging tests are key to the diagnosis of BCS and include ultrasound, CT, MRI, and digital subtraction angiography (DSA). Ultrasound is the preferred screening method, while CT and MRI can fully visualize the intrahepatic vascular anatomy, and DSA is the “gold standard” for diagnosis. Imaging manifestations include liver enlargement or atrophy, hepatic vein and inferior vena cava obstruction, collateral circulation formation, ascites, etc. BCS needs to be differentiated from other liver diseases such as cirrhosis, and the combination of imaging and clinical manifestations can improve the diagnostic accuracy.