Abstract: Liposarcoma is a malignant soft tissue tumor from fat tissue. Commonly it is found in the abdominal cavity or extremities, but they can be found anywhere in the body. They are typically large tumors and not usually spread beyond its local limits. The cause is unknown but has been linked to genetics and some inherited diseases. The tumor may be present for a long time before being diagnosed. Treatment usually involves surgery and potentially radiation. We report a case of giant retroperitoneal sarcoma in a 44 yr old female. Patient was treated effectively with surgery and radiation. Patient followed up to 16 months postoperatively with no local recurrence.