Abstract: In structural optimization, applied loads are usually assumed to be static for most practical applicationseven though in a dynamic case. The results show that the static optimizationusing a dynamic factor cannot properly account for the effects of a dynamic response. Thepresent study performs the dynamic response optimization with equivalent staticloads, which generate the same displacement field as that under dynamicloads. This algorithm is a transformation of a dynamic load into a set ofequivalent static loads and a subsequent static response optimization with thetransformed equivalent static loads as a multiple load case. Variousexamples are solved to verify the algorithm. The results are compared tothose under static loads. It is found that the algorithm is valid for verylarge-scale shape optimization problems.