Objective   To define the specific area of cutaneous branches-chain flaps based on the cutaneous perforators of the posterolateral lower leg, and to provide the anatomical basis for taking the cutaneous branches-chain flap.   Methods   A total of 15 fresh adult cadaveric lower legs (2 female, 13 male) with no history of trauma and surgery were studied. 13 specimens were perfused with red latex for microanatomical analysis, and then the outer diameter of the cutaneous branches at the level of deep fascia was measured. Additionally, 2 specimens were perfused with self-curing denture acrylic to get vascular cast mold for observing the linking pattern of the cutaneous perforators.  Results   A total of 67 cutaneous perforators came from the posterolateral lower leg was observed in our study, with an average (5.15±1.86) on each side;  the diameter of perforators at the deep fascia was（0.92±0.25） mm; The length of fibula was (34.78±17.78) cm. There are 34 cutaneous perforators participating in the formation of branches-chain, with an average (3.31±1.65) on each side; the diameter of perforators was（0.99±0.23） mm; the area of branches-chain of the posterolateral lower leg ranged from (28.33±17.79)% to (64.04±19.48)%.   Conclusion   The cutaneous branches-chain flaps based on the cutaneous perforators of the posterolateral lower leg could be harvested to expand the range of skin flap and ensure safety for harvest of the flap.