TWI838530B

To provide a method of cutting a workpiece that can easily detect the size of a wafer. A method of cutting a workpiece includes: a holding mechanism for holding the workpiece having electrodes in the plural regions divided by the plural preset lines to be cut that cross each other; a cutting mechanism equipped with a cutting blade that cuts the workpiece held by the holding mechanism; a photographing mechanism for photographing the workpiece; a cutting device, which controls the holding mechanism and the control mechanism of the cutting mechanism, divides the workpiece into multiple wafers, detecting the actual sizes of the wafers, and has: a step of cutting the workpiece into the plurality of wafers with a cutting blade along the preset lines to be cut; an image obtaining step of photographing the wafer with a photographing mechanism to obtain the image of the wafer; a detecting step of using the control mechanism to detect the actual sizes of the wafers based on the images.