A portable electronic device including a body, a door, a carrier and at least one electronic module is provided. The door is movably mounted on the body. The carrier includes a first side and a second side opposite to each other, the first side is pivoted to the body, and the second side is movably pivoted to the door. The electronic module is disposed on the carrier. At least one opening is formed between the door and the body when the door moves away from the body, and the door drives the carrier to rotate relative to the body, such that the electronic module is tilted with respect to the body along with the movement of the door, and the electronic module is exposed to an external environment via the opening for heat dissipation.