A secrecy management information recording device has an information input section which inputs image information printed by a printer and secrecy management information corresponding to the image information, a transport mechanism which receives a printing sheet on which the image information has been printed by the printer, and discharges the sheet after passage over a heat generating resistor, and a magnetic tag forming section which controls generation of heat by the heat generating resistor according to content of the secrecy management information corresponding to the image information printed on the transported printing sheet to thermally transfer at least one magnetic member contained in a thermal transfer sheet onto the printing sheet. A magnetic tag representing the content of the secrecy management information is thereby formed on the printing sheet. This device records additional information corresponding to image information on a printing medium at the time of copying of the image information to the printing medium in such a manner that the additional information is remotely readable.