Provided is a method of preparing a red clay processed material using red clay and sodium hydroxide and a red clay processed material having anti-corrosive and virus disinfecting activity. Also, a method of preparing alkali ionized water having excellent anti-bacterial, virus disinfecting and anti-corrosive activity using the red clay processed material, alkali ionized water using the same, and a functional product including the same are provided. The red clay processed material and the method of preparing alkali ionized water using the same can reduce the reaction temperature and reaction time compared to a conventional process, thereby significantly reducing the production cost. The red clay processed material and the alkali ionized water have excellent anti-bacterial, anti-corrosive, and virus disinfecting activity and are not toxic, so they can be widely applied in various health-care and agricultural, livestock, and marine fields such as an agent for preventing viral infectious diseases, a food preservative, a natural agricultural pesticide or fertilizer, paint, feed, an eco-friendly construction material, a red tide/green tide inhibitor, a cosmetic additive, or an anti-corrosive agent.
