Abnormal linear growth (stunting) is characteristic of children with beta thalassemia major and has been variably and inconsistently attributed to multiple different mechanisms. Despite the coexistence of beta thalassemia with deficits of several micronutrients, global undernutrition as a principle cause of growth abnormalities has not been adequately studied. We prospectively studied 115 nonsplenectomized children (6 months-6 years, 54 males, 61 girls) with beta thalassemia major who has not previously received chelation therapy. Most children had abnormal weight-for-age (WAZ) and height-for-age (HAZ) Z scores, however female children had lower WAZ (p < 0.0001) and HAZ (p < 0.02) compared to males. Mild to moderate degrees of acute wasting was also usual, and two males and one female had severe wasting. Severe weight deficits were more prevalent in the youngest (p < 0.01) and severe stunting in the older (p = 0.01) children. Nearly all children were < 50th percentile for both weight-for-age and height-for-age, and the majority were < 5th percentile. Of note, children were also disproportionately distributed below the 50th percentile for weight-for-height. Pre-transfusion hemoglobin was variably associated with anthropometric measurements. We conclude that not only is linear growth failure pervasive in our population with beta thalassemia major, but varying degrees of wasting are also typical. Further, weight deficits occur at an early age and appear to precede deficits in linear growth. Abnormal growth is not due to chelation therapy and is inconsistently associated with the degree of anemia. These patterns of growth abnormalities indicate general malnutrition as an important cause of growth failure in children with beta thalassemia.