Abstract: It is an important subject to suppress the cavity flow noise of supersonic weapon bay in aviation field. Many studies show that the active/passive control technologies can definitely suppress the noise in the cavity. The large eddy simulation(LES) method was used to compute and analyze the flow and noise at Mach 1.4 in an open rectangle cavity and two kinds of geometrically modified cavities with wavy and curved front/rear walls, which contributes to exploring the ability of geometrically modified passive control technology to suppress the flow noise of supersonic open rectangle cavity. The results show that both the wavy and the curved cavities have suppression effects on the cavity noise. Moreover, the wavy cavity works better than the curved cavity in noise control. The analysis shows that the geometrically modified technology can change the development and evolution of the cavity shear layer and the large-scale vortex structure, and further lead to the control of the cavity noise. In addition, the LES method was also used to compute and analyze the flow in a rectangle cavity with a thickened incoming boundary layer. It is found that the noise in the cavity is significantly reduced by the thickened incoming boundary layer.