Background: Improved survival in patients with β-thalassemia has enabled the appearance of several clinical morbidities, involving renal problems. Incredibly important is the early detection of persons at higher risk of getting renal failure. Aim of work: To compare the sensitivity of KIM-1, NGAL and microalbuminuria in early detection of kidney injury in thalassemic children. Subjects and methods: A cross sectional study was conducted in the Outpatient Clinic of Hematology Unit of Pediatric Department and Clinical Pathology Department at Zagazig University Hospitals on thirty thalassemic patients during their regular follow-up visits and thirty age- and sex-matched healthy children as a control group from June to December 2017. All thalassemic patients were subjected to full medical history. Periodic thorough clinical examination was done with special emphasis on disease-related complications. Routine laboratory investigations were performed in addition to serum concentrations of Neutrophil Gelatinase-Associated Lipocalin (NGAL) protein (ng/ml), urine concentration of kidney injury molecule-1 (KIM-1) and microalbuminuria. Results: A highly statistically significant increase in the levels of urinary KIM-1, serum NGAL and albumin in urine among cases compared to controls was found. We found that the sensitivity of KIM-1 biomarker in prediction of kidney injury among thalassemia patients was 93.3%, higher than sensitivity of NGAL and microalbuminuria biomarkers. Conclusion: In early identification of acute renal failure in thalassemia patients, urinary KIM-1 is more sensitive than serum NGAL and microalbuminuria.