Background: The aim of this study was to investigate the correlation between the cardiac and hepatic iron-overload as assessed by magnetic resonance imaging t2 star (MRIT2-star) technique and serum ferritin level in patients with thalassemia major. Methods: In this cross-sectional study we evaluated 170 patients in Sayed Shohada Hospital in Isfahan in the year of 2009, cardiac and hepatic iron-overloaded values were calculated in patients using magnetic resonance imaging t2 star techniques. Serum ferritin level and left ventricular ejection fraction (LVEF) were determined for all patients. Findings: We studied 170 beta-thalassemic patients, 90 (52.9%) females and 80 (47.1%) males, mean age 20.6 ± 6.2 years. Mean cardiac iron-overloaded was 22.7 ± 14.7, mean hepatic iron-overloaded was 3.2 ± 2.4, mean serum ferritin level was 2310 ± 1554 and mean left ventricular ejection fraction was 60.5% ± 7.7 percent. Pearson’s tests gave a significant correlation coefficient between cardiac iron-overloaded and hepatic iron-overloaded (r = 0.29, P < 0.001). There were weak inversely associated between serum ferritin level with hepatic iron (r = -0.32, P < 0.001) and cardiac iron (r = -0.21, P = 0.006). Conclusion: Myocardial iron deposition can be reproducibly quantified using myocardial  and this is the most significant variable for predicting the need for ventricular dysfunction treatment. The finding of this study demonstrated a significant correlation between cardiac and hepatic iron-overloaded level in patients with thalassemia major. Key words: Cardiac iron overload, Hepatic iron-overloaded, Magnetic resonance imaging-T2 star, Thalassemia.