Nowadays, information security is an important thing. Much confidential information such as personal data, financial data, and even state secrets of confidential data needs to be protected so that it cannot be misused by others who are not authorized to do. One step for maintaining the security of information is by using steganography technique. Steganography image is the development of science from steganography. The first part of this paper explains what steganography means in general. Then proceed with the explanation of the study of the application of steganography on MP3 (MPEG Layer3) audio. Many methods can be used in steganographic techniques on MP3 files as though Least Significant Bit (LSB), Spread Spectrum, Direct Sequence Spread Spectrum (DSSS), Parity Coding, Phase Coding, Echo Hiding, DCT and DWT. The final part of this paper will explain the future work on steganography.