In the present study, the aim was to explore the quality of life of thalassaemia major (TM) patients according to age, sex, school performance, severity and complications of the disease. A cross-sectional descriptive study was conducted. Quality of life was evaluated by 4 questionnaires; demographic characteristics, the short form 36 health survey (SF-36), Persian version of symptoms checklist-90-revised (SCL-90-R) and life satisfaction index (LSI). 687 (41.08%) of the eligible patients with TM completed the questionnaires. With the SF-36 questionnaire, 329 (47.9%) participants had an excellent level of physical functioning. With the SCL-90-R questionnaire, 446 (64.9%) participants had a global severity index of > 0.7, considered psychiatric patients, 141 (20.5%) patients had GSI between 0.4 and 0.7, considered suspected psychiatric patients and 100 (14.6%) participants had GSI of < 0.4, considered non-psychiatric patients. The mean score of LSI questionnaire was 20.50 (SD 5.95), range 2–37. Beta-TM patients are at risk of psychiatric symptoms and need appropriate psychiatric counselling.