Abstract: When flowing in the pipeline, natural gas tends to generate the flow noise due to the effect of turbulence and vortex. T-shape joint is an indispensable component of the pipeline system, so it is of great necessity to study its noise change laws thoroughly. In this paper, the three-dimensional physical model for T-shaped joint was established. Then, based on the FW-H acoustic analogy theory, the change laws of flow noise of T-shaped joint composed of different inlets and outlets were simulated, calculated and analyzed by means of the FW-H model that comes with ANSYS Fluent. It is indicated that when the medium flows in the T-shaped joint, the flow noise of higher level is generated under the effect of vortex near the wall surface and it can easily bring serious harm to the station staff physically and mentally. When there is only one horizontal outlet, the flow noise in the T-shaped joint reaches the highest level, exceeding the national standard of 70 dB. The flow noise level of T-shaped joint can be reduced effectively by changing the combination of inlets and outlets. The numerical computation results provide the theoretical basis for the study and formulation of flow noise prevention and control measures of T-shaped joints at gas stations.