PROBLEM TO BE SOLVED: To provide a low cost, environmentally friendly purifying material for a water purifier which is excellent in anion adsorption, a method of purifying service water using the same and a water purifier. SOLUTION: The purifying material for the water purifier treatment is composed of a carbon material 9S having anion adsorption characteristic by bringing a carbonized material 9 obtained by carbonizing a raw material of plant origin 5 into contact with an acid solution 12 or contains the carbon material 9S. COPYRIGHT: (C)2006,JPO&NCIPI