The present invention provides a technique enabling long-term preservation of a chlorous acid aqueous solution and novel application thereof. A sterilizing agent comprising an aqueous solution comprising chlorous acid (chlorous acid aqueous solution), which is used as a sterilizing agent, comprises a chlorous acid aqueous solution, metal hydroxide, and metal phosphate. Preferably, an agent in which potassium is the metal and/or pH is 3.5 or higher and less than 7.0 is prepared, whereby an unexpected long-term stabilizing effect was demonstrated. Further, the present invention provides: a sterilizing agent for preventing secondary contamination, comprising a chlorous acid aqueous solution, or an article impregnated with a chlorous acid aqueous solution for preventing secondary contamination； an article impregnated with a chlorous acid aqueous solution for sterilizing a floor surface； an agent for removing odor comprising a chlorous acid aqueous solution or an article impregnated with a chlorous acid aqueous solution for removing odor； and an agent for removing microbes adhering to the body, comprising a chlorous acid aqueous solution or an article impregnated with a chlorous acid aqueous solution for removing body adhering microbes.
