A time-dependent information management system and method for a mobile phone that enable the management of time-related information in consideration of a change of time zone are provided. The method includes registering an event planned to occur at a first local time based on a first time zone together with a reference time calculated from the first local time; if the mobile phone enters into a second time zone, selecting the event in accordance with a key input; and setting the event to occur at a second local time calculated from the reference time. The system and method enable selectively adapting, when a mobile phone moves from a first time zone to a second time zone, times of schedules planned in the first time zone to a local time of second time zone, thereby effectively managing the schedules in multiple time zone-crossing environment.