The current report describes the case of a 29-year-old female with a sacral giant cell tumor (GCT) during pregnancy. Originally, the patient presented with severe pain in the lumbosacral region, radiating posterolaterally from the lumbar spine into the bilateral thigh and subsequently, into the bilateral crus posterolaterally. Plain X-rays, computed tomography and magnetic resonance imaging showed osteolytic destruction of the sacrococcygeal bones and a huge soft-tissue mass with features of a chordoma. The patient underwent a partial en bloc sacrectomy (partial S1 and completely below) and curettage for tumors located at the sacroiliac joint and underlying left ilium, with bilateral internal iliac arteries ligated to control intraoperative hemorrhage. The patient's bilateral S2 nerve roots were killed. The diagnosis of conventional GCT was determined based on the histopathological examination of the resected specimen. Urinary and bowel functions were recovered by exercising.