A portable electronic device has various functions such as mobile communication, multimedia entertainment, and data processing. The device includes a main body installed with two keyboards and two slide rails, and two sub-bodies respectively equipped with a display. The sub-bodies are pivoted to each other and rotate through a shaft, and slide along slide rails through connecting members on the main body respectively. Therefore, the sub-bodies can be lifted relative to the main body through the shaft and the connecting members, so as to be optionally drawn close to the main body with the two displays facing the same direction, or to stand on the main body with the two displays facing opposite directions. Therefore, two different operating modes are achieved.