Objective: To investigate the anatomic features of the perforating branch flap of the medial vastus muscle, so as to provide a new perforating branch flap for repairing the soft tissue defect., Methods: Six fresh donated lower limb specimens underwent an intra-arterial injection of a lead oxide and lactoprene preparation. The integument of the thigh was dissected to observe the origin, course, size, and location of the perforating branch of the medial vastus muscle by angiography and photography. Based on the anatomic study, the free perforating branch flaps of the medial vastus muscle (14 cm x 6 cm to 20 cm x 5 cm) were used to repair skin and soft tissue defects (8 cm x 6 cm to 12 cm x 8 cm) of the feet in 4 patients between June 2009 and August 2011., Results: The artery of the medial vastus was sent out constantly from the femoral artery, and then descended in the vastus muscle to lateral patella where it anastomosed with the terminal branches of lateral femoral circumflex artery to form prepatellar vascular network. The artery of the medial vastus sent out 3-5 musculocutaneous perforating branches into the deep fascia and then extended superficially to the overlying skin. Four flaps survived after surgery; wounds at the donor site and recipient site healed by first intention. After follow-up of 6-12 months, the flaps had good appearance and texture. All ankles had normal movement range of plantarflexion and dorsiflexion., Conclusion: The free perforating branch flaps of the medial vastus muscle can be harvested easily, and have the advantage of good texture and abundant donor site.