An audio data storage and playback apparatus is provided, including at least a USB hub or USB SIE, at least a storage media interface, and an audio codec. An upstream port of the USB hub or the USB SIE is connected to an electronic device with a USB interface. The storage media interface is connected to a downstream port of the USB hub or an endpoint of a USB SIE. The storage media interface can be connected to a portable storage media, such as flash memory, CD-R/W, DVD-R/W, and hard disk drive, to enable bi-directional data transmission and storage between the electronic device with a USB interface and the portable storage media connected to the storage media interface. The audio codec player forms a bi-directional data transmission connection with the storage media interface. The audio codec player is connected to at least an audio player and an audio input device. The audio data from the electronic device with a USB interface, the portable storage media connected to the storage media interface or the audio input device can be sent to the audio codec for encoding/decoding, and then stored or played back by the audio player or the electronic device with a USB interface to achieve the object of the present invention of multi-directional transmission, encoding/decoding, storage and playing back of audio data.