The invention discloses a mobile terminal comprising an external mounted side key, a stop block and a housing with a frame; the frame is provided with a mount hole; the external mounted side key comprises a button column; the button column is movably assembled in the mount hole; a portion, penetrating the mount hole, of the button column is matched with the stop block; the stop block and the innerwall of the frame are in spacing cooperation. An existing external mounted side key needs a mount hole with a large opening area, so the housing intensity is weak, and the housing is hard to seal; the mobile terminal can solve said problems.