Giant cell tumor is an uncommon but most aggressive benign tumour of the spine with unpredictable outcome and challenging treatment. Spinal giant cell tumors located above the sacrum are rare and treatment recommendations are still unclear. We report a rare case of this lesion in an adult and discuss the management and outcome of such uncommon tumors. A 31-year-old woman presented with progressive motor weakness of both lower limbs with back pain during the past month, associated with sphincter disturbances for the past two days. She was diagnosed with a lytic heterogeneously enhancing mass depending mainly on the T6 posterior arch with small vertebral body involvement. The tumor extent reached surrounding soft tissue and the spinal canal with marked spinal cord compression. A posterior approach was realized as an emergency. Histological examination showed evidence of a giant cell tumor and a complementary irradiation was used. The patient improved well post operatively. There was no recurrence or metastasis over 5 years of follow-up.