PROBLEM TO BE SOLVED: To provide an epoch-making water absorption treating material exerting an unconventional action effect, and a preservation method of the same. SOLUTION: The water absorption treating material for subjecting an object A to be treated to water absorption treatment includes a water absorbing resin 3 that has water absorbability, and a grainy or powder carbonaceous material 2 that floats on water 1. COPYRIGHT: (C)2013,JPO&INPIT