Abstract: A workpiece grinding method includes a rotary-shaft direction grinding step of grinding a back surface of a workpiece by relatively moving a grinding wheel and a chuck table holding a front surface of the workpiece toward each other along an axis of a rotary shaft of the chuck table, the grinding wheel including a plurality of grinding stones that have outer peripheral surfaces defining a circle of a diameter not greater than a radius of the workpiece, and a radially directed grinding step of grinding the back surface of the workpiece by relatively moving the grinding wheel and the chuck table in a radial direction of the chuck table. The radially directed grinding step includes one of or both an inwardly directed grinding step of relatively moving the grinding wheel and the chuck table, and an outwardly directed grinding step of relatively moving the grinding wheel and the chuck table.