There are provided a mobile terminal capable of switching a function of the mobile terminal depending on whether a sensor is contacted or not contacted, a mobile terminal control method, a mobile terminal control program, and a recording medium. A mobile phone 1 includes a touch sensor 9 at a position where a user generally contacts the mobile phone 1 when the user holds it. While a user is in contact with the touch sensor 9, the mobile phone 1 can perform normal operation. If the mobile phone 1 continues to be not in contact with the touch sensor 9 for a certain time, it switches from the normal operation. For example, assume that a lock mode setting is made. The mobile phone 1 switches to a lock mode while it is not in contact with the touch sensor 9. When the touch sensor 9 is contacted again, the mobile phone 1 shifts to a state for unlock processing such as password entry. If an entry is normally made, the mobile phone 1 is unlocked.