The invention discloses a shortened pulling rope power device. According to the shortened pulling rope power device, a structure body of the shortened pulling rope power device is composed of a rectangular frame provided with a gear set and a supporting frame. The two ends of a rotary shaft of a large gear are each provided with two thin ropes. One or more portions of the four thin ropes are wound around and hung on the two ends of two or more rotary shafts or fixed shafts on the supporting frame. One or more portions of the four thin ropes are wound around and hung on the rotary shafts or the fixed shafts, and therefore one or more portions are bent, the other ends of rubber bands connected to the other ends of the four thin ropes correspondingly are hung on the supporting frame. One or more portions of the four thin ropes are wound around and hung on the rotary shafts or the fixed shafts on the supporting frame to be bent, and therefore the shortened pulling rope power device is short, small and light in structure and good in power operating effect.