Liposarcoma, one of the most common soft-tissue sarcomas, originates from primitive mesenchymal cells, and its diagnostic criteria have been well established. Myxoid liposarcoma is the second most common histological subtype, occurring more frequently during the fourth and fifth decades of life. There are only a few sporadic published cases of spinal liposarcomas, whatever primary or metastatic. We describe an unusual case of primary myxoid liposarcoma of the thoracic spine in a 79-year-old male, presented with a 2-month history of intractable dorsal pain and progressive weakness of lower limbs. Surgical treatment was performed with wide tumor resection, spinal cord decompression, and posterior instrumentation complemented by radiotherapy. Only one other case has been reported with this spinal localization in the literature. Despite its rarity, myxoid liposarcoma should be considered in the differential diagnosis of primary tumors of the thoracic spine.