The present invention provides a safe virus disinfectant. Specifically, the present invention provides a virus disinfectant comprising a chlorous acid aqueous solution for inactivating viruses, such as at least one species of viruses selected from the group consisting of polioviruses, influenza viruses, herpesviruses, noroviruses, and feline caliciviruses. The virus disinfectant comprising a chlorous acid aqueous solution of the present invention can be utilized as a food additive, antiseptic, quasi-drug, medicine, or the like. Although there was an issue of sodium hypochlorite not being safe to a human body (high cytotoxicity), this has been resolved. Chlorous acid, which is safe for a human body and easy to handle and generates little chlorine dioxide, is produced as a virus disinfectant and a sterilizing agent for pretreatment in food processing. Chlorous acid is used as a virus disinfectant or a sterilizing agent.