The presence of osteoclast-like giant cells (OGC) has been reported as a rare and distinct feature in uterine leiomyosarcoma. To present knowledge, 11 cases have been described in the English literature. The authors report an additional example in a 35-year-old woman who presented with a pelvic mass. Pulmonary metastasis was detected by the preoperative CT scan. The hysterectomy specimen revealed a 11.5 cm intramural mass with hemorrhagic and necrotic center. The histologic examination revealed pleomorphic sarcoma with OGC. The neoplastic cells were immunoreative for smooth muscle actin and desmin. Minor intermixing component of conventional leiomyosarcoma and leiomyoma were identified at the periphery of the malignant component. The patient died of disease after 16 months of diagnosis. To our knowledge, this is the youngest case of uterine leiomyosarcoma with OGC. Leiomyosarcoma with OGC has an aggressive clinical course. The tumor may occur in young patient and may arise from pre-existing leiomyoma.