Objective To introduce the anatomical study and clinical experience of medial retromalleolar perforator adipofascial flap. Methods Microsurgical anatomic study was carried out on 24 fresh cadaver limbs, and was focused on the distal perforators of the posterior tibial artery. Then five clinical cases of distally based medial retromalleolar perforator flaps were raised for medial wound coverage of the calcaneus after open fracture. Results The terminal part of posterior tibial artery run distally in the medial retromalleolar space. The space was usually 4cm long, with its anterior border of medial malleolus and flexor digitorum longus tendon, medial border of Achilles tendon, covered by deep fascia, and filled with areolar fatty tissue. In the space, there were about 2~3 fasciocutaneous perforators with caliber ranged 0.1~0.7 mm, usually less than 0.5mm with an average 0.47mm. The perforating artery usually had one partner veins. These perforators showed apparent link-anastomosis with the mostdistal septal perforator of posterior artery. In clinic, the five flaps, measured 5~6cm×6~12cm with pivot point 1~2 cm above the tip of medial malleolus, survived completely and smoothly. This adipofascial flap, compared to distally based faciocutaneous flap, has obvious advantages of reducing the morbidity to lower leg donor site, releasing venous drainage load, improving survived quality. Conclusions The retromalleolar perforator adipofascial flap is a thin reliable, pliable flap with an easy and simple surgical process. It should be considerated for medial aspect of the foot and heel.