A wafer dicing method includes preparing a wafer having a plurality of device formation areas and a scribe lane area defining the plurality of device formation areas, forming a plurality of semiconductor devices in the plurality of device formation areas of the wafer, forming, in the scribe lane area, a plurality of first grooves partially passing through at least a portion of the wafer in a vertical direction, forming a plurality of second grooves by planarizing lower surfaces of the plurality of first grooves, forming one or more internal cracks in the wafer by radiating a laser beam along lower surfaces of the plurality of second grooves, and separating the plurality of semiconductor devices from each other along the one or more internal cracks.