According to one embodiment, a cleaning apparatus includes a removing unit whose tip portion is harder than a constituent material of a surface layer on a back surface side of a semiconductor wafer (wafer) and which is configured to clean a back surface of the wafer held by a holding unit and a moving mechanism that relatively moves the removing unit and the wafer in a direction parallel to the wafer back surface. The removing unit grinds and removes a protrusion that is formed of a material same as the surface layer of the wafer back surface, by the moving mechanism relatively moving the removing unit and the wafer and causing the tip portion of the removing unit to come into contact with the protrusion.