Abstract: In order to study the influence of different humidity environment on the flow field performance and aerodynamic noise of a counter-rotating axial-flow fan in the mine, the flow field of the fan is numerically simulated with large eddy simulation and FW-H acoustic model under the relative humidity of the environment was 0, 25%, 50%, 70%, 80%, 90% and 100%, and vortex structure and aerodynamic noise variation in internal flow field is analyzed. The results show that with the increase of relative humidity, and the static pressure, power and efficiency of the fan decrease roughly in a linear trend, the intensity of tip leakage vortex decreases. At the monitoring points of inlet and outlet, the average sound pressure level decreases to varying degrees. When the relative humidity increases by 10%, the pressure rise decreases by about 2.08%, the power decreases by about 1.9%, the efficiency decreases by about 0.57%, and the sound level A at each monitoring point decreases by 0.9%.