An exemplary electronic device includes a cover, a circuit board and a driving module both mounted on the bottom cover, an electronic component fixed on the circuit board, a heat dissipating plate mounted on the circuit board and thermally contacting the electronic component, and a top cover covering the bottom cover. The driving module has a rotating shaft adapted for supportively driving an optical disk to rotate. The electronic component generates heat during operation. Through holes are defined in the top cover and located at a periphery of the rotating shaft. Two opposing elongated extending portions extend downwardly from the heat dissipating plate towards the circuit board. An airflow channel is formed between the two extending portions under the heat dissipating plate and aligned with the electronic component.