In order to distinguish leakage noise and valve noise, provide a theoretical basis and the database for leak detection and location based on acoustic method and provide methods to control valves noise, the paper makes a study on aero-acoustics induced by gas flowing through valves in gas pipelines in view of sound generation mechanism and builds a aero-acoustics mode from which the aero-acoustics noise generation, transmission and attenuation disciplines can be concluded. First the transient flow field such as fluctuating pressure and fluctuating velocity is obtained with large eddy simulation model by computational fluid dynamics software when gas flows through valves in gas-pipelines. Then the data is imported into acoustic BEM software SYSNOISE to carry through numerical analysis and transformed into dipole source and quadrupole source. And the aero-acoustics model is built to solve the aero-acoustics problems. Finally the aero-acoustics noise generation, transmission and attenuation disciplines are concluded.