During flap elevation, most perforators are cut except one or more perforators that are essential to flap survival. However these cutout perforators can cause deterioration of the blood circulation of the flap. To salvage the jeopardized flaps, rebuilding the perforator system is essential for flap survival. In the first case, after flap elevation, the upper abdominal flap margin was severely ischemic. To supply blood to the upper abdominal flaps, we found and used a major perforator underneath the upper abdominal flap which was cut earlier during the elevation, and we performed reanastomosis with ipsilateral deep inferior epigastric artery. Upper abdominal flap ischemic area was limited to a narrow suture area. In the second case, we performed free superficial inferior epigastric artery (SIEA) flap reconstruction. After successful anastomosis of the SIEA and superficial inferior epigastric vein (SIEV) with internal mammary artery and vein, serious venous congestion occurred immediately because of SIEV malfunction. We found the largest perforator vein under the flap, as an alternate way to drain, then connected it with the thoracoacromial vein with a vein graft harvested in the contralateral SIEV. Circulation has improved. In conclusion, perforator system reconstruction is essential in a jeopardized flap salvage.