This study aims to explore the anatomical characteristics and clinical application of a medial tarsal free venous flap. We identified communicating venous systems in deep and superficial layers of anatomical specimens and tissue sections of the skin and subcutaneous tissue of the medial tarsal region. Based on this anatomical feature, we designed and cut free venous flaps in the medial tarsal region, suturing a vein in the deep layer of the flap to an artery of the hand, and suturing the shallow layer of the flap to a dorsal vein or palmar superficial vein of the finger, to repair soft tissue defects of the palmar fingers. We performed this procedure in 63 cases, and all flaps survived. There was no postoperative congestion or necrosis, as commonly seen in "non-physiological flaps." These cases were followed up for 3 months to 2 years, with good color, elasticity, and appearance of the flaps, and no significant effect on the donor feet. The venous structure of the deep and shallow layers of a medial tarsal free flap and the communicating veins between the 2 layers are very important anatomical features, enabling better effective blood perfusion within the flap, as compared to a traditional venous flap. The application of this "similar physiological flap" enabled a satisfactory outcome.