There have been few reports documenting primary myxopapillary ependymomas in the sacrococcygeal region that result in extensive involvement of the sacrum. We present a 21-year-old man whose CT and MR findings showed massive bony destruction of the sacrum and a large lobulated soft tissue mass. Myxopapillary ependymoma should be included along with giant cell tumor, chordoma, and aneurysmal bone cyst in the differential diagnosis of a destructive osteolytic sacral lesion.