This study investigated the clinical application of anterolateral thigh (ALT) perforator flap in reconstruction of soft tissue defect of lower extremity. There were twenty-one patients who had been taken soft tissue reconstruction with anterolateral thigh perforator flap. There were 19 males and 2 females between 3 and 65 years (mean, 36 years). This study included 4 cases of pedatric case of under 10-year-old. All cases were a cutaneous flap. Flap size averaged $160;cm^2;(20{sim}450;cm^2)$. 19 cases were musculocutaneous perforator flaps and 2 were septocutaneous perforator. T-shaped pedicle were used to reconstruct and to preserve major artery of lower extremity in 2 cases. 19 cases flaps survived completely and 2 cases flap were marginal necrosis partially. There was venous congestion in one case of type of reverse island flap but that was improved after salvage procedure with leech. While the donor sites were closed directly in 5cases, 16 cases underwent skin graft. ALT flap is suitable for coverage of defects in lower extremity where have various condition and reliable in children as in adult.