A foldable portable terminal device is disclosed. In one aspect, the device includes a flexible display configured to display an image and a foldable body accommodating the flexible display on a front side thereof. The device also includes first and second guide members disposed on opposing sides of the flexible display, wherein the first and second guide members are disposed on the front side of the body and extend in a length direction of the body. A first region of the body is configured to be folded so as to face a second region of the body. The first and second guide members are configured to guide an end of the first region to move in the length direction of the body while maintaining a predetermined interval with respect to the second region.