Giant cell tumor (GCT) is considered a locally aggressive, intermediate grade benign bone neoplasm. In rare cases, GCT undergoes malignant degeneration or may cause distant metastasis, mainly in the pulmonary area. Most bone GCTs are situated in the epiphysis or metaphysis of long bones, while GCTs of the pelvis are quite rare. There is no standard treatment protocol for the GCT of pelvic bones. This paper presents the therapeutic management of a rare case of a stage III GCT, situated on the iliac tuberosity, sacral wing and partially the left iliac wing. The chosen treatment consisted in intralesional curettage, high-speed burring, phenolization and hydrogen peroxide lavage. At the six-week follow-up, the patient reported minimal disability. No complications and no local infections were revealed. Healing was confirmed by the two-year postoperative follow-up. This case report demonstrates that intralesional curettage complemented with adjuvant therapies is a viable alternative to wide resection surgery for the treatment of aggressive GCT.