The invention belongs to the technical field of grinding equipment, and discloses a vehicle tire grinding device, which comprises a base, a rotating shaft is movably sleeved in the middle part above the base, and the upper part of the base extends to the right through the rotating shaft and is fixedly installed with a fixed Axle 1, a fixed shaft 2 is fixedly installed on the right end face of the rotating shaft in a circumferential array, a belt motor is fixedly installed on the lower part of the base, and a belt is connected between the belt motor and the rotating shaft, and the right end of the fixed shaft 1 is movable Set with support rim. In the present invention, the fixed shaft 1 is fixedly installed with the base. After the supporting rim rotates, the fixed shaft 1 rotates relative to the supporting rim, thereby driving the transmission teeth to rotate, and driving the rotating sleeve to rotate, so that the supporting plate slides on the inner surface of the tire, and the supporting plate is always maintained. Support in the original position, that is, the grinding block 1 and the grinding block 2 are always supported by a support plate in the grinding part of the tire during the rotating grinding process of the tire, which ensures the smoothness of the tire surface grinding.