A method for cleaning a skid of a surface roughness tester including the skid provided with a skid aperture in a vertical direction, and a stylus disposed in the skid aperture of the skid and capable of moving in the vertical direction, wherein the surface roughness tester measures surface roughness of an object by moving the skid along a surface of the object. The method includes removing a foreign substance existing in a gap between the skid aperture and the stylus after measuring the surface roughness of the object.