Background: The purpose of this study is to determine the clinical characteristics and management of portal vein thrombosis (PVT) after splenectomy for thalassemia major. Methods: Patients with thalassemia major who had the diagnosis of PVT following splenectomy defined by colour Doppler ultrasound at the Children Hospital 1 from January 2008 to December 2011 were reviewed in a retrospective study. Results: 11 out of 175 patients with thalassemia major had PVT following splenectomy. Age, female, splenic mass and high ferritin level were risk factors associated with PVT. Abdominal pain, fever and vomiting were common manifestations among patients with PVT following splenectomy. Patients with PVT had postoperative white blood cell count and platelet count significantly higher than those without PVT. Early anticoagulation therapy with lowmolecular-weight heparin (LMWH) and vitamin K antagonists achieved complete resolution at 63.6 percent, partial resolution at 9.1 percent and cavernous transformation of the portal vein, at 9.1 percent. Conclusion: Early diagnosis of PVT following splenectomy for thalassemia major and anticoagulation therapy could result in complete recanalization of the portal vein.