The authors present surgical therapy of liposarcoma in retroperitoneum. These mesenchymal tumors occur rarely in the population. The strategy for therapy requires determination of the relations to adjacent organs on the basis of precise preoperation examination of the patient. Surgery is considered as the basic therapy, provided radical extirpation of the tumor is possible. Our case report describes a huge liposarcoma in retroperitoneum with histology evolving from myxoid to low differentiated liposarcoma of retroperitoneum. The repeated relapse of the tumor was, as fart as possible, treated by extirpation of the tumor.