Guy device for a pole driven into the ground, particularly a support pole (10) for vine-growing plants, comprising an anchoring member (14) driven deeply into the ground, a connecting member (15) whose lower end is hooked to the anchoring member (14) and whose upper end is connected through a tensioning member (16) to the pole to be guyed. Both the connecting member (15) and the tensioning member (16) are made of a metal wire or cable, or equivalent material folded so as to form respective closed annular elements, the wire of the connecting member (15) passing through a seat obtained in the anchoring member (14) and having the ends reciprocally knotted, and the tensioning member (16) being hooked to the connecting member (15).
