A purifying agent or the like which can improve purifying performance is obtained. A container (12) of a purifying agent generating apparatus (10) contains a solution (14), into which a surface-active agent has been dissolved, and ozone gas is supplied thereto. In this way, a purifying agent (34) (i.e., aggregate of ozone-containing bubbles (32), each of which includes an ozone-containing membrane, into which ozone has been dissolved, and ozone-containing gas, which is contained in the inner portion of the membrane and includes ozone) is generated. Therefore, odor which fills a sealed space can be removed and a higher purifying performance is obtained.