Charged fine particulate water is provided, which has a nanometer particle size, for example, a particle size of 3 to 100 nm, and contains radicals such as hydroxyl radicals and superoxides. This charged fine particulate water can be generated by applying an electric-field intensity of 700 to 1200 V/mm between a pair of electrodes, while supplying water between the electrodes. By allowing the thus obtained charged fine particulate water to diffuse into an indoor space, it is possible to effectively remove bad odor components/bacteria from the indoor space.