A gas adsorption material has a three-dimensional structure wherein a ligand (p-hydroxybenzoic acid) having an aromatic ring as a principal skeleton containing, a carboxyl group and a functional group capable of forming a coordinate bond, the functional group being other than the carboxyl group, and a metal nucleus (Zn) are bonded to each other at a ratio of 1:1. The ligand contains a functional hydroxyl group other than the carboxyl group, and the carboxyl group and the functional group other than the carboxyl group are bonded in at least one position to the metal nucleus. The gas adsorption material is produced by drying a precursor obtained by reacting the ligand and the metal nucleus, dissolving the dried precursor in an organic solvent, heating and stirring a resultant solution to form a three-dimensional structure that includes the organic solvent as a crystal solvent, and removing the crystal solvent.