Introduction: Major beta thalassemia is a type of autosomal recessive disorder characterized by ineffective erythropoiesis. Constant injections and the body's inability to remove iron from the body lead to an overload of iron, which can damage heart tissue. One of the regulatory pathways for heart disease through iron accumulation is the Osteoprotegrin / RANK pathway (Receptor ACTIVATOR of Nuclear FACTOR k_B / RANKL Receptor ACTIVATOR of Nuclear FACTOR Ligand). The purpose of this study was to investigate the serum level of RANKL and its association with left ventricular hypertrophy (LVH), diastolic dysfunction, mutation, pulmonary hypertension, and MRIT * 2 in major thalassemia patients. Be. HBV. Materials and Methods: This study was performed in descriptive manner on 82 patients with thalassemia major in Kilink Server Mashhad in 1396. All patients were evaluated completely and non-invasively (complete 2D echocardiography and color M-Mode Doppler and MRIT * 2). The ELISA technique was used to measure serum RANKL levels. Spss20 was used for statistical analysis. Results: Out of 82 patients, 36 were women and 46 were men. The mean age of the patients was 23. 6 83 6. 83 years. Left ventricular hypertrophy and diastolic dysfunction were present in 24 patients (29. 30%) and 23 patients (28%), respectively. There was no significant association between RANKL serum and left ventricular hypertrophy, diastolic dysfunction, mutation deficit, pulmonary hypertension, MRIT * 2 index (p <0. 05). Conclusion: Research has shown that there is no significant relationship between serum RANKL levels and severe left ventricular hypertrophy, diastolic dysfunction, jump deficit, pulmonary hypertension, MRIT * 2 index, which is the result of more research in this regard. He calls.