Growth failure is one of the most common problems in children with thalassemia with multiple etiologies. We present a case of celiac disease, an underdiagnosed cause of growth failure in a child with β-thalassemia major. A 10-year-old boy on a hypertransfusion regimen was referred for early onset growth failure. Serology for hepatitis B, hepatitis C, and HIV was negative. Serum zinc levels were normal. Thyroid function tests and growth hormone secretion, evaluated with clonidine stimulation test were normal. Malabsorption syndrome was suspected, even in the absence of gastrointestinal symptoms. Tissue transglutaminase were highly raised >300 IU/mL (normal values <15 U/L). Characteristic mucosal lesions on jejunal biopsy confirmed the diagnosis of celiac disease. Institution of a gluten-free diet resulted in rapid gain in weight and improvement in height velocity.