A portable electronic device including a first body, a second body, and at least one speaker is provided. The second body is pivotally connected to one side edge of the first body, such that the second body is selectively rotated to cover the first body, or to form an angle with respect to the first body. The speaker is movably disposed on an upper surface of the first body, and can be moved relative to the first body. Thus, the speaker can be moved and fixed to a predetermined position to achieve optimized output sound quality.