Abstract: A mobile phone with antitheft function and an antitheft method thereof are provided. The mobile phone enters antitheft mode if the mobile phone has not been moved outside a user's registered geographical range for more than a predetermined time period and outputs an alarm sound and transmits current location information and images photographed around the mobile phone if detecting a movement of the mobile phone so that a user can easily locate his mobile phone. Furthermore, the mobile phone does not allow anyone other than the user to move or use the mobile phone, and photographs the attempter, carries out face recognition based on the photographed image and outputs a predetermined alarm message.