Objective　To provide anatomical basis of medial femoral condyle periosteal flap pedicled with the infrapatellar branch of the descending genicular artery for reconstruction of the knee joint.　Methods  30 embalmed lower limbs of adult cadavers perfused with the red latex were used for this anatomical study. The adductor tubercle and medial femoral codyle were observational landmarks, the followings were observed: the course, branch and distribution of the branch of the desceding genicular artery to the knee joint.　Results　The articular branch of descending genicular artery above the inferior edge of medial femoral condyle (5.9±1.2)cm always gives off two mian branches: the periosteal branch and the infrapatellar branch. The original diameter of the periosteal branch is（1.3±0.2）mm, and it travels along the medial femoral condyle (4.8±1.1)cm in length; the original diameter of the infrapatellar branch is(1.3±0.2)mm, and its length is (6.6±1.5)cm.　Conclusion　The medial femoral condyle periosteal flap pedicled with the infrapatellar branch of the descending genicular artery can be developed to repair bone injuries of knee joint.