Moving pictures experts group(MPEG) series standards have become one of the most popular families in the field of multimedia application. MPEG audio is an elementary part of these standards. With the normalization of new standards such as MPEG-4/7/21 in the recent several years, a novel multimedia application interoperability framework will be founded. However, many attentions should still be concentrated on improving the efficiency of audio coding and on mining more precise content-based description methods. A detailed review of the techniques and developments of MPEG audio standards was made, and possible problems of existing standards were pointed out. The conclusion and a brief description of the perspectives of MPEG audio were given.