Paraganglioma is a rare neuroendocrine neoplasm observed in patients of all ages but it has not been characterized in children. The authors describe a retroperitoneal paraganglioma diagnosed by chance in an 11-year-old boy. Many aspects of retroperitoneal paraganglioma are still under investigation. The treatment of choice is radical resection. Surgery may be possible following chemotherapeutic debulking with cyclophosphamide, vincristine, and dacarbazine. 131I-MIBG radiotherapy has proved increasingly useful in reducing the pain associated with disseminated disease and also in facilitating surgical resection in cases that appear inoperable. Conventional radiotherapy is purely palliative and used to reduce the pain of bone metastases.