Disclosed is a mobile terminal. The mobile terminal may comprise a card slot and controller. The card slot may have any one of a plurality of identity module cards in each of which user ID information and a different Operating System (OS) are stored mounted thereon. The controller may execute the OS stored in the mounted identity module card and perform user certification on the basis of the user ID information stored in the mounted identity module card, when the one identity module card is mounted on the card slot.