PROBLEM TO BE SOLVED: To provide a laser marking processing method for applying long-term maintainable and visibility-improved character and pattern to a fiber structure which contains moisture and is covered with at least one of the skin or a film in the vicinity of a surface layer.SOLUTION: A laser beam having a wave length of any of 2.6 μm or more and 3.5 μm or less or 5.6 μm or more and 6.8 μm or less or 8.8 μm or more and 10.9 μm or less or having an absorption factor to water of 100 mmor more, is applied to a fiber structure which contains moisture and which is covered with at least one of the skin or a film in the surface layer vicinity, and a pattern of combining a dot or a straight line or a curve or these is marking-processed by impregnating or sticking or burying at least one of a dye or a pigment or a chemical or a food product or a food additive in a fiber-like part exposed by vaporizing the moisture of the fiber structure.SELECTED DRAWING: Figure 4
