A portable terminal device includes: a first member having a keyboard operation portion; and a second member having a display portion and attached to the first member via a coupling member movable in a horizontal direction relative to the first member, the second member being movable together with the coupling member in the horizontal direction relative to the first member. The second member is rotatably attached to the coupling member so that a side face or a rear face of the second member is allowed to face forward after the coupling member is moved in the horizontal direction relative to the first member. It is also possible to attach the coupling member to the first member so as to be slidable in one direction or rotatable in the horizontal direction, and to attach the second member to the coupling member to be rotatable in the horizontal direction.