Soft-tissue defects caused by radiation injury are a challenging task for the reconstructive surgeon, due to the extent of the soft-tissue damage and the associated injuries of the local blood vessels and bone tissue. We present the application of the versatile deep inferior epigastric perforator (DIEP) flap for the coverage of an extended lateral thigh soft-tissue defect after the surgical resection of an undifferentiated pleomorphic high-grade sarcoma, neoadjuvant chemotherapy, and adjuvant chemo- and radiotherapy. A double-pedicled free DIEP flap (756 cm2) was harvested and anastomosed to the transverse branch of the lateral femoral circumflex artery and a lateral branch of the popliteal artery (P1). The flap survived completely without serious complications, and the patient was able to walk with crutches 3 months postoperatively. This is the first case report of a free bipedicled DIEP flap for the coverage of a thigh defect in a male patient.