The invention relates to a grooved pulley sliding cable device. A hanging and dropping cable can be embedded when an upper and a lower rocker arms extend (are separated), and the ends of the rocker arms are provided with guide pulleys; when the upper and the lower rocker arms hold the grooved pulley, the dropping cable is led to be wound in the circumferential groove of the grooved pulley; and a large circumference wrap angle holding friction force of the cable wound in the circumferential groove is utilized. Meanwhile, the gliding speed can be controlled by the grooved pulley sliding cable device tied in front of a chest of person through the brake control of a brake disc which is coaxially fastened with the grooved pulley, so that the person can safely slide to the ground from a balconyor a window.