The present invention is intended to provide an active exercise apparatus for lower limbs that allows a user to perform on a floor lower limb active exercise highly effective in preventing thrombosis. An active exercise apparatus for lower limbs 10 includes, for example, a base body 1； a shaft 2 fixed to the base body 1 such that a central axis is vertical to the surface of the base body 1； arms 3a and 3b that are rotatably attached to the shaft 2 and are extended in two directions at an equal angle with respect to the central axis of the shaft 2； sole support plates 4a and 4b that are attached to leading ends of the arms 3a and 3b and rotatable by rotation axes x1 and x2 parallel to the surface of the base body 1 and the rotation axes z1 and z2 vertical to the surface of the base body 1； and reaction force exertion members that are installed on the back surfaces of the sole support plates 4a and 4b to exert a reaction force on backward rotation by rotation axes x1 and x2 parallel to the surface of the base body 1.
