Abstract Background: Thalassemia is a hereditary autosomal recessive hematological condition, which is identified by a genetic abnormality in hemoglobin chains. It is typified by iron overload, persistent anemia, reduced oxygen transport to tissues, and rapid hemolysis due to red blood cell dysfunction. Every year, over 68,000 newborns are born with different thalassemia disorders. It is predicted that 80 to 90 million people globally are carriers of beta-thalassemia, which accounts for 1.5% of the world's population. Purpose: This study was intended to explore the impact of thalassemia on cardiopulmonary capacity and functional performance in children. Methods: The published research in PubMed, LILACS, Google Scholar, and Cochrane Library Scholar that studied thalassemia was reviewed with the following keywords: pulmonary function, exercise tolerance, functional performance, quality of life, and social participation. Studies that met the current research's criteria were included; those that didn't were not. Results: The reviewed studies demonstrate that children with thalassemia exhibit impaired cardiopulmonary exercise testing and capacity and reduced pulmonary function. Beta-thalassemia has a negative impact on functional capacity, routine activities, and quality of life, which reduces functional performance. Conclusion: The reviewed studies highlight that children with thalassemia often present with reduced exercise tolerance and impaired functional performance due to chronic anemia, iron overload, and musculoskeletal complications. These factors not only compromise their physical capacity but also limit participation in routine activities and overall quality of life.