Abstract: The problem on the acoustic radiation of a simply supported concrete shell with stiffened bars and ring ribs,which is submerged in air,is difficult to be solved analytically,since the influence of the stiffened bars and ring ribs increase the complexity of the system's resonant spectra.In this study,the finite element analysis program ANSYS is applied to investigate the impact of the internal air and the number of the ribs on the acoustic characteristics of the sound radiation from the shell.And the results indicate that in the range of low frequencies,the influence of the internal air on the acoustic radiation characteristics of cylindrical shells is very small.In addition,adding appropriate ribs may reduce the sound pressure level of the structure-radiated noise.