BACKGROUND AND OBJECTIVES: Budd-Chiari syndrome (BCS) is a rare disorder caused by obstruction to hepatic venous outflow. It affects all races, usually during the third or fourth decade of life. Higher prevalence had being evident in developing countries. The aim of the present study was to clarify sociodemographic features, clinical, radiological presentations, and etiology of BCS among Upper Egyptian patients. PATIENTS AND METHODS: This retrospective cohort study enrolled 50 Upper Egyptian Patients with confirmed primary BCS. Liver, coagulation, and thrombophilia workup profiles were performed as anticardiolipin antibodies, lupus anticoagulant, protein C, protein S, and antithrombin III assays. Factor V Leiden and JAK2 mutations were assessed. Full radiological assessment was done. RESULTS: Fifty patients were included. There were 28 males (56%) and 22 females (44%) with mean age (32.5 ± 11.1 years). The etiological factor was not identified in 22% of cases (n=11). Isolated factor C deficiency was found in 26% (n=13) with male predominance 39.3% and protein S deficiency in 10% (n=5). Factor V Leiden mutation was the etiology in 5 patients (10%). Membranous web and antiphospholipid syndrome each were the etiology in 8% (n=4). Behςet's disease was diagnosed in 4% (n=2). Cases of liver cirrhosis(LC) were 41/50(82%)they were :33/50(66%) LC child class C, 8 /50(16%)  LC child class B, and 0/50 (0%) LC child class A. Abdominal pain was the most common symptom (96%), and ascites was the most common sign (82%). Obstruction of hepatic veins was present in 80%. CONCLUSION: BCS in Upper Egyptian patients was mainly occurred in males in the third and fourth decade of life, mostly with liver cirrhosis. The most common etiology is isolated protein C deficiency followed by Factor V Leiden mutation and isolated protein S deficiency. Hepatic veins obstruction was the most common pattern of vascular involvement.