To relate to a head liquid which is supplied to efficiently remove ink residues and the like which are attached to the surface of an inkjet head provided with ejection openings through which an ink containing a color material is ejected. In a case where a nonvolatile solvent such as glycerin is used as the head liquid, the nonvolatile solvent absorbs moisture, and thereby an extremely large change in mass is exhibited. As a result, the above supply amount is varied. To solve the problem, it was found that the previous mixing of water with the nonvolatile solvent can provide a smaller change in mass than that in a case where the nonvolatile solvent by itself is caused to absorb moisture. Accordingly, a mixture prepared by mixing the nonvolatile solvent and water in an appropriate predetermined ratio is used as a head liquid.