A workpiece cutting method includes attaching a tape to a lower surface of the workpiece, holding the lower surface through the tape on a holding table including a holding plate, at least a part of a holding surface of the holding plate being an imaging area formed of a material transparent to visible light, cutting the workpiece held on the holding table to divide the workpiece, thereby forming a dividing groove, and imaging at least a part of the dividing groove from a upper surface side of the workpiece by using an upper camera portion located above the holding plate, thereby obtaining an upper image, and also imaging the above part of the dividing groove from the lower surface side of the workpiece through the imaging area of the holding plate and the tape by using a lower camera portion located below the holding plate, thereby obtaining a lower image.