A sharing management method for sharing a terminal with plural users includes: after completion of login to an operating system of the terminal or after booting up the operating system, starting to record log data for predetermined events; and after the completion of the login to the operating system or after booting up said operating system, prohibiting an operation other than predetermined operations including user authentication in a sharing management program, wherein the user authentication is other than authentication in the operating system. Then, the log data after the user authentication succeeded includes a user identifier in the sharing management program, which relates to a user whose user authentication succeeded. As a result, while ensuring the security in the terminal apparatus shared by plural users, it is possible to rapidly carry out user switching.