The vibroacoustic performance of plates can be altered by different methods known as structural dynamic modification methods. One of these methods is the shape modification of plate surface. In this study, a method for reducing the sound radiation of vibrating plates is presented. The method based on creating dimples on the surface of a plate. The dimple can be defined as a local modification in the surface of a structure, which has a spherical shape. The dimples change the local stiffness of the plate without changing its mass. Also, they alter the mode shapes so as to reduce sound power, i.e., the radiated sound at some modes is inefficient due to low net volume velocity. The design method couples finite element method, for predicting plate vibration response, with optimization technique based on a genetic algorithm to minimize sound power radiation. The sound radiation is minimized either at a single frequency, or over a broad frequency band. The results show that dimples forming on the plate can achieve effective reductions in radiated sound power.