Abstract: The iterative process of conventional frequency-domain method for simulating artificial ground motions is inefficient. To solve this problem, this paper proposed a new method considering iterative correlation and phase spectrum to generate artificial ground motion, targeting at design response spectrum in Specifications for Seismic Design of Highway Bridges and representative response spectra for nuclear plant equipments, and then discussed the charac-teristics of conventional method and the improved method. The result shows that new method achieves a significant improvement in simulation precision, especially in high frequency and low frequency ranges. Meanwhile, the method has a better performance in highway bridge response spectrum simulation than nuclear plant representative response spectrum simulation.