An auxiliary equipment for valve grinding is provided, including a main body, a driving shaft, a first linkage, a second linkage, a third linkage and a driven shaft. The driving shaft defines a first axial direction. The driving shaft is for connecting to a rotating tool. One end of the first linkage is connected to the driving shaft. The second linkage and the other end of the first linkage are connected to a first movable connecting portion. One end of the third linkage and the second linkage are connected to a second movable connecting portion. The driven shaft defines a second axial direction. When the first linkage rotates together with the driving shaft, the first movable connecting portion rotates about the first axial direction, the second linkage swings about the first movable connecting portion, and the second movable connecting portion swings about the second axial direction.