Abstract: The present invention relates to an ankle joint orthosis (1), which consists of an ankle part (2) that is fixed around the lower leg, and a foot plate (3), which is placed against the sole of the foot. The foot plate (3) and the ankle part (2) are on one side connected with each other by a pivot joint (6) and on the other side connected with each other by two straps (7, 8). The first strap (7) extends essentially vertically from the ankle part (2) to the foot plate (3), whereon it is fixed, whereas the second strap (8) from a common junction (9) extends obliquely to the front part of the foot plate (3). From the common junction (9) a third strap (10) originates, which is braced by a clasp (11) being arranged on the ankle part (2).