Portal vein thrombosis (PVT) consists of two different entities: acute PVT and chronic PVT. Acute PVT usually presents as abdominal pain. When the thrombus extends to the mesenteric venous arches, intestinal infarction can occur. Chronic PVT is usually recognized after a fortuitous diagnosis of hypersplenism or portal hypertension, or when there are biliary symptoms related to portal cholangiopathy. Local risk factors for PVT, such as an abdominal inflammatory focus, can be identified in 30% of patients with acute PVT; 70% of patients with acute and chronic PVT have a general risk factor for PVT, most commonly myeloproliferative disease. Early initiation of anticoagulation therapy for acute PVT is associated with complete and partial success in 50% and 40% of patients, respectively. A minimum of 6 months' anticoagulation therapy is recommended for the treatment of acute PVT. For patients with either form of PVT, permanent anticoagulation therapy should be considered if they have a permanent risk factor. In patients with large varices, beta-adrenergic blockade or endoscopic therapy seems to prevent bleeding as a result of portal hypertension, even in patients on anticoagulation therapy. In patients with jaundice or recurrent biliary symptoms caused by cholangiopathy, insertion of a biliary endoprosthesis is the first treatment option. Overall, the long-term outcome for patients with PVT is good, but is jeopardized by cholangiopathy and transformation of underlying myeloproliferative disease into myelofibrosis or acute leukemia.