This paper described a type of MP3 player based on a SOC-type MCU and the design of its hardware and software in detail.The system realized the decoding of audio files existed in storage medium SD card by making use of a master-control unit called C8051F020 and encoder-decoder chip named as VS1003B.Owing to the application of dedicated audio decoder chip,the system performed well in the respect of playing different kinds of audio files and acoustic fidelity.Through a series of hardware and software testing,...