Abstract: The artificial knee joint for an artificial leg includes a pair of substantially parallel pivotable bars which are connected by pivoting joints to an upper part and a lower part of the knee joint, respectively. One of the bars is anterior and the other is posterior with respect to a position of the artificial leg. The upper part has two spaced pivoting joints and the lower part has two spaced pivoting joints. The imaginary connecting line between the pivoting joint of the anterior bar and the pivoting joint of the posterior bar is substantially horizontal when the leg is in its vertical position. The imaginary connecting line between two pivoting joints of the anterior bar is inclined at a small angle to the imaginary connecting line between two pivoting joints of the posterior bar.