Cable Bead for Tire and Radial Tire using the same

The present invention relates to a cable bead core for a tire and a radial tire using the same, which are able to make up for the weak points of a core wire, thereby increasing the strength of a cable bead unit and improving ride comfort. According to the present invention, the cable bead core for a tire comprises : a core wire; and an external side wire which is twisted by winding the core wire. The core wire is manufactured by die casting by using magnesium or a magnesium alloy. The core wire is manufactured by using one or more of aluminum, manganese, silver, zinc, silicon, or rare earth metals by within 2 wt%. An external surface of the external side wire is plated with brass, bronze, or zinc. According to the present invention, the cable bead core for a tire and a radial tire using the same are able to make up for the structural weak points of the core wire, to increase the strength of a cable bead unit, and to reduce and absorb vibration, thereby improving ride comfort.