Giant cell tumour of bone (GCTB) is a highly vascular tumour, sporadically complicated by massive bleeding during surgery. We report a rare case of GCTB in an HIV-positive patient who suffered massive blood loss intra-and postoperatively. The patient was a 46-year-old HIV-positive female with symptoms and signs of a pelvic mass, and ultrasound evidence of an ovarian mass. Surgery was performed, and a highly vascular retroperitoneal mass originating from her sacrum was identified. Massive blood loss occurred, which required aggressive resuscitation and transfusion of blood products. Damage control surgery was performed, and bleeding was ultimately only controlled postoperatively using bilateral internal iliac artery radiological embolisation. The patient suffered acute kidney injury, which was multifactorial in aetiology, which recovered within 6 days. She was discharged from ICU in a stable condition 7 days postoperatively.