Objective: The aim of this investigation was to study the effect of vitamin E treatment in oxidative stress of red and white cells of β-thalassaemia intermedia patients. Methods: Nine patients undergoing occasional transfusions (5 females/4 males), median age 39 years (range 15–74), were recruited for oral daily administration of 400 IU vitamin E for 3 months. Twenty-seven milliliters of peripheral blood was obtained before and after 3 months of treatment, and 3 months after treatment completion. In the case of transfused patients (n = 4), blood was obtained at least 30 days after transfusion. Reactive oxygen species (ROS) was measured by flow cytometry; red blood cell (RBC) reduced glutathione (GSH) was measured by dinitrothiocyanobenzene reduction, serum malondialdehyde was measured in terms of thiobarbituric acid-reactive substances (TBARS), and α-haemoglobin-stabilizing protein (AHSP) mRNA expression was measured by real-time polymerase chain reaction of reticulocyte RNA extracts. Results: β-Thalassaemia patients presented basal levels of RBC ROS, GSH and serum TBARS statistically different compared with healthy controls. However, after vitamin E administration, patients presented a significant reduction in erythrocyte RBC ROS and serum TBARS levels. In parallel, red cell GSH was significantly increased after treatment. Peripheral mononuclear cells and T lymphocytes also demonstrated a reduction in ROS production. Therefore, after treatment, no significant differences were detected comparing patients and normal controls. Three months after treatment completion, all measurements showed a tendency of returning to basal values. A significant reduction in reticulocyte number was observed after vitamin E treatment. Vitamin E treatment did not modify levels of haemoglobin or AHSP mRNA expression. Conclusion: Although vitamin E is not capable of reducing anaemia in these patients, it could be useful for reducing oxidative damage in other target organs of β-thalassaemic patients. Finally, this is the first study to analyse the effects of vitamin E on ROS production in red and white blood cells and AHSP mRNA expression.