Objective　To provide anatomic basis for clinical application of island flap pedicled with perforator arising from middle-distal part of the anterior tibial artery and running through the anterior septum. Methods　The location, external diameters, concomitant venae, course, length, anastomosis and distribution were observed on 40 sides of adult cadaveric leg specimens fixed by Formalin and perfused with red latex; and 4 sides of fresh leg specimens perfused with Latex-BaSO4 were angiographied.　Results　The anterior tibial artery mainly gives off two perforators in the anterior septum: the anterior septocutaneous perforator from distal part of anterior tibial artery and superficial peroneal artery. The origin of the former perforator is（14.9±3.2）cm above the tip of the lateral malleolus，present in 70% of 40 specimens with an external diameter of (1.0±0.4)mm. 96.4% of them are accompanied by 2 venae comitantes with an external diameter of (1.1±0.4)mm and (0.8±0.2)mm, 3.6% of them are accompanied by 1 concomitant vena. The perforator ramifies into ascending and descending branches after coursing along the anterior septum for about (2.5±0.4)cm; both the ascending and descending branches run parallel with the superficial peroneal nerve, with the ascending branch anastomosing with the superficial peroneal artery; the external diameter of the anastomotic artery is (0.6±0.2)mm. The origin of the superficial peroneal artery is (4.9±2.6)cm below the head of fibula, which is present in 95% of cadaver dissections with an external diameter of(1.4±0.4)mm; 76.3% of them have 2 venae comitantes with the external diameter of (1.7±0.5)mm and (1.3±0.4)mm, 23.7% of them are accompanied by 1 concomitant vena with the external diameter of (1.7±0.8)mm. An arterial arch is formed by anastomosis of the superficial peroneal artery and the ascending branch of the anterior septocutaneous perforator from distal part of the anterior tibial artery. Conclusions　Three types of anterolateral island flaps of the lower leg can be designed to repair skin defects around the distal and the anteromedial part of the lower leg and the patellar region: Skin defects around the malleolus can be repaired with the flap pedicled with the anterior septocutaneous perforator from distal part of the anterior tibial artery by rotating its ascending branch distally; When rotating the perforator and its two branches medially, it can be used to repair large sized skin defects; Pedicled with either of the two perforators and rotate its branch proximally, skin defects around the knee can be repaired. The blood supply of the flap is definite and the main artery of the lower leg is not sacrificed.