The invention relates to a tyre anti-skid device which comprises a conical gear and a plurality of helical gears and is characterized by further comprising a fixed disk, a positioning disk and a plurality of sets telescopic arm equipment, wherein a plurality of supporting plates are installed around the front side end of the fixed disk at a certain equal distance interval, a bearing seat is installed on the front middle part of the fixed disk, an integrally formed sleeve pipe is arranged at the rear end of a middle opening of the conical large gear, the rear end of the sleeve pipe is longitudinally distributed, an inner ring of the bearing on the front middle part of the fixed disk sleeves the rear end of the sleeve pipe, and the helical gears are annularly distributed at the side end of the conical large gear; and the rear ends of the telescopic arm equipment are installed at the front ends of the helical gears correspondingly, an internal thread pipe is installed on the inner side ofthe bearing seat located on the front middle part of the fixed disk, the rear end of the fixed disk is installed in the internal thread pipe, and the fixed disk is installed at the middle of the inner side of a vehicle hub. When a vehicle of the tyre anti-skid device travels, the pointed cone part of the outermost end of a rectangular movable rod can be effectively inserted in the surface of snowor ice, vehicle tyres are prevented from skidding during traveling, and therefore safe running of the vehicle on the snow-covered and ice-covered ground is effectively improved.