Hemostatic parameters of 495 beta-thalassemic patients (421 with thalassemia major and 74 with thalassemia intermedia) were analyzed, to assess their association with the described thrombophilic condition and to verify the role of additional risk factors (e.g. persistent postsplenectomy thrombocytosis, insulin dependent diabetes mellitus, estrogen-progestin treatment and atrial fibrillation). The prevalence of thromboembolic accidents was 5.2% and in four patients (15.3%) inherited or acquired predisposing defects were recognized. The incidence of thromboembolic events and the associated relative risk due to hemocoagulative abnormalities in these patients are discussed.