The invention provides a U-shaped elastic screw for a suspension insulator hanging point of a transmission line tower. Two thread sections are arranged on the upper portion of the U-shaped elastic screw and mounted on tower hanging point angle iron in a penetrating mode. Lower gaskets are mounted on the plane of the tower hanging point angle iron, pressure springs are mounted on the upper portions of the lower gaskets, and upper gaskets are mounted on the upper portions of the pressure springs. Nuts are mounted on the upper portions of the upper gaskets. Pins penetrate through the upper ends, extending from the upper portions of the nuts, of the U-shaped screw. Due to the facts that the U-shaped elastic screw is mounted on the tower hanging point angle iron in the penetrating mode and the pressure springs are mounted between the two corresponding gaskets of the U-shaped elastic screw, the U-shaped elastic screw can adapt to the weight change of an insulator on the lower portion of the hanging point and can balance hanging force of the hanging point insulator when disturbed by external force, a transmission line is buffered and balanced, and the hanging force is regulated. The U-shaped elastic screw is suitable for the suspension insulator hanging point of the transmission line tower.