A workpiece dividing method includes: a laser processing step of forming along each street a plurality of minute holes extending in a pulsed laser beam application direction; and a dividing step of pressing the streets by a pressing member to divide a wafer along the streets. The minute hole has one end opening at least one of a front surface and a back surface of the wafer and is decreased in diameter from the one end toward the other end. In the dividing step, the pressing member is pressed against that surface of the front surface and the back surface of the wafer at which the one end of the minute hole is not opening.