Liposarcomas comprise about 20% of soft tissue sarcomas and occur in 14% in the retroperitoneal space originating in one third from the perirenal fat. The case of a patient with an extraordinary huge, resectable, well-differentiated retroperitoneal liposarcoma is reported. The presenting symptoms were abdominal pain and distension as well as weight gain. Magneticresonance imaging revealed a huge retroperitoneal tumor suspected of well-differentiated liposarcoma. Curative resection of the tumor could be obtained. Only 50% of all tumors are excised without residual tumor and recurrence, occurring in 90% after 10 years, is the main therapeutic challenge. Since neoadjuvant and adjuvant therapy as well as intraoperative radiotherapy failed to prove prognostic value, curative resection remains the main treatment for primary and recurrent liposarcomas.