The long period stage of acceleration design response spectrum (ADRS) in current standards is too short and there are two very different conclusions about raising and reducing its value; Meantime, the values of characteristic period (T_g) and dynamic magnification factor (b ) of ADRS are also in dispute. In this paper, 421 Wenchuan earthquake main shock records from China Strong Motion Network Center (CSMNC) database are selected. These seismic records are classified according to the PGA, site and classification of design earthquake. Response spectrum of conventional seismic records and long-period seismic records are computed and compared with ADRS in current standards. Meanwhile, the DRS fitting model is obtained by using these records based on the a_max-Tg four stages model and Genetic Algorithm(GA), the parameters of the response spectrum model are calibrated and verified, The suggested amendments for characteristic parameters of ADRS are brought up. The results show that the spectral value of long-period stage of conventional seismic records are lower than the ADRS in current standards, however, the spectral value of long-period stage of long-period seismic records is higher than the ADRS in current standards. It reveals why there are two different viewpoints on the value of the long period stage of ADRS in current standards. The fitting ADRS coincides with the actual response spectrum which is better than that with standard ADRS; It explains the necessity to supplement the ADRS of long-period ground motions and provides a reference for revision of the specification DRS.