To determine the incidence of lymph node metastasis in patients with osteogenic sarcoma, a careful study was carried out of the femoral, iliac, and the axillary lymph nodes of all the patients treated by modified hemipelvectomy and interscapulothoracic amputation. Lymph node metastasis appears to be more common than expected and should be considered when a curative approach is intended. © 1969.