β-thalassemia syndromes are the most common inherited anemia disorders, caused by impaired β-globin chain synthesis. The patients with thalassemia major have severe anemia along with tissue deposition of iron, due to multiple transfusions, wish is the main cause of multiple organ dysfunctions, especially in the cardiovascular, endocrine and hepatic systems. The aim of this study was to evaluate renal function in beta thalassemia patients using conventional tests (as creatinine, urea, microalbuminuria) and early markers(as N-acetyl-beta- D-glucosaminidase ) of renal dysfunctions, and to correlate results with clinical parameters. 170 β-thalassemia patients (aged 4-28 years) and 30 healthy controls (aged 4-28 years) were enrolled in this study .Blood samples were collected and serum was separated for measurement of creatinine, urea, and ferritin. Urine samples were also collected for measurement of albumin and N-acetyl-beta-D-glucosaminidase ( NAG). There was a significant increase in serum creatinine, and Albumin: Creatinine ratio (microalbuminuria) in beta thalassemia patients when compared with their control (p=0.017 and p<0.0001, respectively). NAG activity levels were elevated in beta thalassemia patients compared with control group (mean ± SD:13.69± 10.85 U/L and 3.77±1.86 U/L respectively) and were correlated to ferritin levels (r=0.579, p<0.0001).On the other hand, there were no significant changes in serum urea in beta thalassemia patients when compared with their controls (p=0.480). In thalassemia patients, Albumin: creatinine (A:C) and NAG showed significant positive correlation with blood transfusion (r=0.578,p<0.0001 and r=0.734, p<0.0001, respectively) and age (r=0.586, p<0.0001 and r=0.735, p<0.0001, respectively). As a Conclusions Renal tubular dysfunction is a common complication in beta thalassemia patients, without clinical manifestation of renal dysfunction. Therefore it is recommended to investigate presence of severe renal dysfunction in thalassemic patients, using sensitive and specific tests, mainly NAG, to prevent progress towards the complications.