Objective　To offer anatomy basis for the lateral dorsal of pedis island flap by discussing the composition of the lateral dorsal artery chain.　Methods　Anastomosis, distribution and external diameters of calcaneus branch of lateral posteror malleolus artery, descending branch of the lateral anterior malleolus artery, the lateral tarsal artery and the fourth metatarsal dorsal artery were observed on 48 sides of adult cadaveric foot specimens.　Results　Calcaneus branch of lateral posteror malleolus artery was the terminal branch of the peroneal artery, with the external diameter of （1.0±0.3）mm. The external diameter of descending branch of lateral anterior malleolus artery was （1.3±0.3）mm. The descending branch was along the anterior edge of lateral malleolus which divided into anterior and posterior branch at the level of prominence of the malleolus. The posterior branch anastomosized with calcaneus branch of lateral posteror malleolus artery, with the occurrence rate of 97.9% and the external diameter of （0.8±0.3）mm. The anterior branch and lateral tarsal artery formed the arterial arch, with the occurrence rate of 91.6% and the external diameter of 0.6±0.2）mm. The lateral tarsal artery divided into 1 anastomotic branch with arcuate artery or the fourth metatarsal dorsal artery, with the occurrence rate of 95.8% and the external diameter of （0.6±0.2）mm. The sensation innervation of pedis island flap was as follows: the lateral edge of the foot was supplied by nervus cutaneus dorsalis lateralis pedis accompanied by lateral calcaneal artery, the anterolateral edge by skin branch from nervus cutaneus dorsalis intermedius pedis.　Conclusions　The artery chain of lateral dorsal on foot consists of lateral calcaneal artery, descending branch of the lateral anterior malleolus artery, lateral tarsal artery and the 4th metatarsal dorsal artery, which expand the dissection boundary of lateral foot flap and increase the flexibility of clinical application.