Giant cell bone tumors are the most common precursor lesions of aneurysmal bone cysts (ABCs) developing secondarily. In giant cell bone tumors containing an explicit ABC component, the observation of the solid component of the giant cell bone tumor plays a critical role in the separation of the primary ABC. In general, ABC cases together with giant cell tumors in the bone are diagnosed histopathologically. The combination of giant cell bone tumor with superposed ABC and that of painful scoliosis with backache is rarely seen in children. In this case study, we discussed the diagnosis and the treatment of a giant cell tumor and superposed an ABC present in the fifth lumbar spine in a pediatric patient admitted to our clinic with a complaint of acute scoliotic back pain.