Abstract: Dynamic orthosis for drop foot, with a vertical flat, rigid bar connected to a collar of a patient's leg, and whose lower free end is connected to a bearing which is positioned in front of the internal malleoulus of the user and to constitute the joint of a cantilevered arm whose free end is connected to a bracket for the foot, and whose motion required for lifting the foot during deambulation is obtained by the force generated by a magnetic spring with the interposition of a rod, wherein the required lifting force are produced by a plurality of magnets, vertically aligned in a cylindrical sheath, and with the same polarity being juxtaposed to allow using their mutual repulsive forces.