Anti-skid device for a wheel of a vehicle, comprising: - a first arc element apt to be mounted at a first side of said wheel, whose ends (12a, 12b) define a first gap; - a second arc element apt to be mounted at a second side of said wheel, whose ends (22a, 22b) define a second gap; - a bridge element apt to connect said first and second arc elements (11, 21) in such a way as to distance them on planes substantially parallel one to the other, with the gaps (18, 28) arranged with substantially identical radial orientation; - an anti-skid element between the first and second arc elements (11, 21) apt, in a mounted condition of the device, to be arranged on the surface of the tread of said wheel; wherein the arrangement of said bridge element divides the first arc element into a first branch and into a second branch and the second arc element into a first branch and into a second branch; characterised in that an extendable cable having a first and a second end is provided; the first end of said cable is fixed in a point of the first branch of the first arc element; the cable goes beyond the first gap, follows the entire length of the second branch of the first arc element and via said bridge element reaches the second arc element; it travels the entire length of the second branch of the second arc element, goes beyond the second gap and reaches a tensioning device provided in a position of the second branch, at which it is fixed with its second end; said tensioning device being apt to tension the extendable cable once the anti-skid device has been mounted on the wheel, reducing said first and second gaps (18, 28) in order to fix said arc elements (11, 21) on the inner and outer sides of the wheel, placing itself on the sides of the tyre. - a first arc element apt to be mounted at a first side of said wheel, whose ends (12a, 12b) define a first gap; - a second arc element apt to be mounted at a second side of said wheel, whose ends (22a, 22b) define a second gap; - a bridge element apt to connect said first and second arc elements (11, 21) in such a way as to distance them on planes substantially parallel one to the other, with the gaps (18, 28) arranged with substantially identical radial orientation; - an anti-skid element between the first and second arc elements (11, 21) apt, in a mounted condition of the device, to be arranged on the surface of the tread of said wheel; wherein the arrangement of said bridge element divides the first arc element into a first branch and into a second branch and the second arc element into a first branch and into a second branch; characterised in that an extendable cable having a first and a second end is provided; the first end of said cable is fixed in a point of the first branch of the first arc element; the cable goes beyond the first gap, follows the entire length of the second branch of the first arc element and via said bridge element reaches the second arc element; it travels the entire length of the second branch of the second arc element, goes beyond the second gap and reaches a tensioning device provided in a position of the second branch, at which it is fixed with its second end; said tensioning device being apt to tension the extendable cable once the anti-skid device has been mounted on the wheel, reducing said first and second gaps (18, 28) in order to fix said arc elements (11, 21) on the inner and outer sides of the wheel, placing itself on the sides of the tyre. wherein the arrangement of said bridge element divides the first arc element into a first branch and into a second branch and the second arc element into a first branch and into a second branch; characterised in that an extendable cable having a first and a second end is provided; the first end of said cable is fixed in a point of the first branch of the first arc element; the cable goes beyond the first gap, follows the entire length of the second branch of the first arc element and via said bridge element reaches the second arc element; it travels the entire length of the second branch of the second arc element, goes beyond the second gap and reaches a tensioning device provided in a position of the second branch, at which it is fixed with its second end; said tensioning device being apt to tension the extendable cable once the anti-skid device has been mounted on the wheel, reducing said first and second gaps (18, 28) in order to fix said arc elements (11, 21) on the inner and outer sides of the wheel, placing itself on the sides of the tyre.