The invention discloses a grinding wheel fixing device for an edge grinding machine. The grinding wheel fixing device comprises a fixing seat. The fixing seat is mounted on the outer circumference of a fixing ring. The fixing ring is mounted on the outer side of a gear fixing device. The end face of one side of the fixing seat is in flush with the end face of the outer side of the fixing ring. A mounting hole is formed in the middle of the fixing seat. A movable shaft is mounted in the mounting hole. A grinding wheel mounting shaft is arranged at the end, located on one side of the gear fixing device, of the movable shaft. A grinding wheel is arranged at the lower end of the grinding wheel mounting shaft. The end of the movable shaft is connected with the grinding wheel mounting shaft through a universal joint coupling. By the adoption of the grinding wheel fixing device for the edge grinding machine, the position and the angle of the grinding wheel are adjusted extremely flexibly, and the edge grinding requirements of gears on different diameters, different thicknesses and different tooth shapes can be met.