Secondary cancer is a serious late complication in childhood leukemia survivors. Here, we report a case of secondary skull sarcoma developing after treatment for childhood acute myeloid leukemia, including bone marrow transplantation (BMT). This patient had breast cancer 1 year before treatment for the skull sarcoma. The patient underwent macroscopic total removal of the skull tumor with bone margin with postoperative radiation therapy and did not develop tumor recurrence for 25 months. Our patient's experience suggests that survivors of childhood leukemia are at risk of developing skull sarcoma and that multi-agent chemotherapy, including anthracycline, TBI used as conditioning for BMT, and development of GVHD, are possible risk factors. Considering the possibility of multiple secondary malignancies in such patients, careful long-term follow up is mandatory.