Abstract: The invention concerns an apparatus for cleaning the edge of a wafer that may be relatively simply constructed with low cost, and prevent the wafer from being re-contaminated by the edge cleaning, thus resulting in increase of the yield rate of wafers. The apparatus includes a cleaning agent ejection nozzle body provided on a side part of a chuck for ejecting a particulate cleaning agent (CO2 particles) towards the side and the edge portions of the wafer held and rotated by the chuck, and a nozzle body carriage for moving the nozzle body between rest and cleaning positions.