A mobile terminal is provided. The mobile terminal includes a terminal body having a case that forms an exterior of the terminal body and a slot portion formed in the case, a socket mounted in the terminal body, the socket being configured to receive an external device through the slot portion, a slide door arranged behind the slot portion, the slide door being configured to slide to expose and cover the socket and a first spring coupled to one side of the slide door. When the external device is connected to the socket, the external device maintains the slide door in an open position and, when the external device is removed from the socket, the first spring provides a restorative force to move the slide door into a closed position covering the socket.