Background: Thalassemia, one of the most common genetic diseases globally, can contribute to physical developmental delays in pediatric patients due to various factors. Chronic anemia, transfusional iron overload and chelation toxicity are key influences on the growth of children with thalassemia. Objective: This study aims to describe the physical development of pediatric thalassemia patients and assess the factors associated with their physical indices. Methods: A cross-sectional study involving 44 pediatric thalassemia patients receiving treatment at the Pediatric Center, Hue Central Hospital, was conducted from February 2023 to December 2023. Results: The study included 44 participants with an average age of 7.5 ± 4.3 years and an equal distribution of males and females. Of these, 64.5% were transfusion-dependent thalassemia patients. Serum ferritin levels exceeded 1000 ng/ml in 43.2% of participants, and the mean hemoglobin concentration was 67.4 ± 16.1 g/L. Of the evaluated children, 31.8% had height-for-age below -2SD, and 43.2% had weight-for-age below -2SD. Statistically significant associations were observed between height-for-age, weight-for-age, and both blood transfusion dependence and serum ferritin concentration (p < 0.05). However, no significant differences were detected between physical indices and disease type or hemoglobin concentration (p > 0.05). Conclusions: This study found that 31.8% of pediatric thalassemia patients experienced stunting, and 43.2% experienced wasting malnutrition. The degree of blood transfusion dependence and serum ferritin concentration were identified as factors associated with a higher prevalence of stunting and wasting malnutrition in children with thalassemia. Key words: Children, thalassemia, physical index, transfusion-dependent thalassemia, non-transfusion-dependent thalassemia.