An information discriminating device includes an information acquiring unit, an information discriminating unit, and an information superimposing unit. The information acquiring unit acquires private information to be privately used by a user of the information discriminating device. The information discriminating unit discriminates a public information portion that is also usable as public information accessible by a special majority in the private information acquired by the information acquiring unit from a private information portion unusable as the public information. The information superimposing unit superimposes the private information portion on the public information.