Diastolic functions of left ventricle was studied in 50 b -thalassemia major patients whose age was > 5 years taken from hematology clinic of Cairo University Pediatric Hospital using E, A waves; E/A; Edt and Tie index as indicators for diastolic function. The study revealed diastolic dysfunction of impaired relaxation pattern in patients whose age was > 10 yaers or their serum ferritin level was 1000 ng/ ml but there was no significant correlation between any of these variables and the changes in parameters of distolic functions