Abstract: A computational model of T-matrix method to calculate the acoustic scattering from the subm-erged rigid objects with arbitrary shapes is established. Making use of the geometric symmetry of the objects,many simplifying methods for calculations of Q matrix have been presented. The backscattering and forward scattering functions of finite cylinders with hemispheroidal end caps,which have different ratio of length to width or different geometric end caps,were calculated. Physical interference model between the specular reflection and Franz wave by finite cylinders,and the effect of the length of cylindrical portion on scattering field have been discussed further. Meanwhile a reasonable physical explanation on the obtained calculated results has been given. The calculated results also show that T-matrix method is an easy and practical method,which could be used to calculate the far field acoustic scattering from subm-erged objects.