A wafer manufacturing method for manufacturing a wafer from an ingot includes forming a peeling layer within the ingot by positioning a condensing point at a depth corresponding to the thickness of the wafer to be produced, and irradiating the ingot with a first laser beam, forming a character, a number, or a mark representing information regarding resistivity in or on the ingot by positioning a condensing point in a region in which devices are not to be formed and irradiating the ingot with a second laser beam, and dividing the ingot with the peeling layer as a starting point.