Objective To explore the effectiveness of modified anterolateral thigh perforator flap pedicled by cross-bridge microvascular anastomosis in treatment of soft tissue defects in the middle and lower segments of the leg. Methods Between March 2011 and June 2015, 15 cases with skin and soft tissue defects in the middle and lower segments of the legs were treated. There were 9 males and 6 females, aged 22-48 years (mean, 32.6 years). Of whom, 8 patients caused by traffic accidents, 5 by machine twist, and 2 by crash injury of heavy object. The mean interval from injury to admission was 82.6 hours (range, 2 hours to 1 week). The area of defect ranged from 13 cm×9 cm to 23 cm×16 cm. After primary debridement and vaccum sealing drainage treatment, the defects were repaired with modified anterolateral thigh perforator flap pedicled by cross-bridge microvascular anastomosis. The size of flap ranged from 15 cm×10 cm to 25 cm×15 cm. The donor sites were sutured directly or repaired with the skin grafts. The pedicle division was done at 4 weeks after operation. Results After operation, venous crisis occurred in 1 case and distal skin necrosis in 2 cases which was healed by dressing change. The other tissue flaps survived successfully and wounds healed by first intention. All skin grafts at donor site survived after operation, and primary healing of wound was obtained. All patients were followed up 6-24 months (mean, 13 months). All flaps were characterized by soft texture, satisfactory appearance, and restoring the protective sensation. Moreover, the two-point discrimination ranged from 15 to 28 mm (mean, 19.5 mm) at 6 months after operation. The function of both lower extremities were normal without obvious contracture of scar at donor site. Conclusion Modified free anterolateral thigh perforator flap, with little damage in donor site, a reliable blood supply by making a cross-bridge microvascular anastomosis with pretibial or posterior tibial blood vessel on normal leg, is a reliable alternative method for repairing soft tissue defects with the main vessels of serious injury in the middle and lower segments of the leg.