Purpose: Multi-organ hemosiderosis is a known complication in thalassemia patients with chronic blood transfusion. T2-Star (T2*) MRI has been introduced as a non-invasive tool for detecting iron overload in the liver and heart in these patients. This study is to determine and assess renal iron overload by MRI and its relation to liver and heart iron and serum ferritin in Iranian thalassemia patients. Methods: Total 821 transfusion dependent major and intermediate thalassemia patients (age range 10-50 years) were included in this study and calculations were done on their MRI data in a medical imaging center through 2014-2016. Iron values were calculated and averaged in a different region of interests (ROI) using fast-gradient-echo multi-echo T2* sequences. Results: Pathological renal iron content less than 36 ms was around 19.6%. The mean T2* kidney of the total population was 50.26 ms. A moderate negative, statistically significant correlation between kidney T2* relaxation time and serum ferritin was noted. For liver and heart, T2* relaxation time weakly, a statistically significant correlation was acquired by renal T2* relaxation time. Conclusions: Renal hemosiderosis was shown in numerous thalassemia patients. Since the frequency of renal iron deposition was approximately 20% in TM patients in a general population study, it might shed light that frequently monitors the renal iron loading merit hematologists in preventing the secondary side effects.