Abstract: A new numerical method of acoustic scattering in fluids is presented. Radiation boundary condition (RBC) is applied to confine acoustic scattering problem in infinite space to finite space. Coupled with RBC and boundary condition on the surface of scatterer, Helmholtz equation in the finite region is solved numerically by the finite lifference method. Thus the distribution of surface field and near field can be obtained..Numerical results for sphere and prolate spheroid are in excellent agreement with those obtained by the eigenfunction expansion method and much better than the results for OSRC method. This method may be a valid alternative to the traditional analytical and numerical methods.