Abstract: The formulas for sound generation by uniform flow past moving body in two dimensions are derived. The sound generation induced by the flow past aerofoil in two dimensions is studied. The results show that the sound pressure changing with time is different at different Reynolds numbers. It is regular at small Reynolds number while it becomes irregular at large Reynolds number, which due to interaction among different vortex at large Reynolds numbers. The amplitude induced by flow past vibrated aerofoil is larger than that induced by flow past stationary aerofoil. The contribution of monopole to the sound is not negligible.