I comprises an organic compound and inorganic particles, unsaturated chemisorbed to the inorganic particles, and an oxygen absorption promoter. The oxygen absorber can be produced by a manufacturing method including a step of chemically adsorbed on the inorganic particles and the organic unsaturated compounds. In accordance with the present invention, the oxygen absorber can be constructed of the resin composition having high oxygen absorption capacity, and the resin composition of the oxygen-absorbing using the same and the resulting packaging material.無機物粒子と、該無機物粒子に化学吸着した不飽和の有機化合物と、酸素吸収促進剤とを含む。この酸素吸収剤は、不飽和の有機化合物を無機物粒子に化学吸着させる工程を含む製造方法によって製造できる。本発明によれば、酸素吸収能の高い樹脂組成物を構成できる酸素吸収剤、および、それを用いた酸素吸収性の樹脂組成物および包装材が得られる。
