Abstract: The design ground motion time histories was synthesized for the Shahuan Nuclear Power Plant Site according to the characteristics of the site and the specifications of input motion in the paper. The acceptability of synthetic time histories for the specified criteria by U. S. NRC Standard Review Plan and ASCE4 86 Standard SASRNS and Commentary on Standard for SASRNS was also discussed from the total time duration, the envelop design response spectra, the frequency intervals in the computed spectra and spectral values, adequately matching a target PSD function compatible with the design response spectra and the input motion time histories to be statistically independent and so on.