Lipoblastoma is a rare benign tumor of adipose tissue seen almost always in infanthood and early childhood. It is typically located in the extremities and the trunk and less frequently in the head-neck region, mediastinum, and retroperitoneum. However, cases of pleural, thoracic wall, and pulmonary lipoblastoma have also been reported in the literature. Lipoblastoma is a tumor with good prognosis despite its potential for local invasion and rapid growth. Our patient is a 7-month-old girl who was brought to our clinic for a rapidly growing mass in the right hemithorax. With the aim of both diagnosis and treatment, the mass was removed by thoracic wall resection and the resultant defect covered with an absorbable polyglactine mesh. The excised mass was diagnosed pathologically as a benign lipoblastoma. In the postoperative period, the thorax wall was stable, and after 24 months of follow-up no recurrence was observed. In the literature, 4 types of thoracic wall lipoblastomas have been reported, but thoracic wall resection has not been applied in any benign lipoblastoma case. To the best of our knowledge, the only benign lipoblastoma case in which a thoracic wall resection was carried out, with its clinical and histopathologic specifications alongside that in the literature, is presented here for the first time. (C) 2004 Elsevier Inc. All rights reserved.