Abstract: The continuum structural-acoustic topology optimization under external loading is investigated herein. Finite Element Method (FEM) is used to obtain the structural frequency response and Boundary Element Method (BEM) is adopted to perform exterior acoustic radiation analysis. The Evolutionary Structural Optimization (ESO) is served as an optimization method in structural-acoustic radiation topology analysis. The acoustic radiation optimization of a plate under harmonic excitation is given for example. The numerical results show that using ESO solution to analyze structural-acoustic topology optimization is feasible and effective.