A mobile phone and a location update method adapted for the mobile phone are provided. The mobile phone includes a location update processing unit, a location area judging unit, a scope acquiring unit, a scope judging unit, and a selecting unit. When the mobile phone frequently moves back and forth within a predetermined scope of a boundary area of two adjacent location areas, the mobile phone does not perform a location update, and thus the mobile phone does not need send updated location information to a network server and saves a lot of power.