Abstract: In this paper, PEER ground motion database(PGMD) at the Pacific earthquake engineering research center (PEER) was updated by 141 groups of ground motion records in Japan Tohoku earquake on March 11, 2011, building an attenuation model of acceleration response spectrum of M_W9.0, having expanded the limitation of this database. Following the disaggregation results from probabilistic seismic hazard analysis, the scenario earthquake and the conditional mean spectrum (CMS) were set up as the target requirement and the selection, and scaling of ground motions for the great scenario earthquake was addressed finally. The results show that the expanded database could reflect the different selection and scaling of strong motion records in great earthquakes, and the suggested method could be applied to the structural spectrum analysis.