Abstract: It is well-established that the spectral period range is one of the critical considerations in ground motion scaling. However, there is no consensus and quantitative basis in current codes for seismic design of buildings. In the paper, first of all, correlation analyses are carried out between acceleration spectrum corresponding to different periods and structural non-linear seismic responses. The preliminary spectral period range is discussed, which makes a significant contribution to the structural non-linear seismic response. Then, based on extensive statistics analysis and normalization processing, the parameter proxy of spectral shape is introduced to decouple the control action of S_a(T₁). Finally, some suggestions are presented to determine the range for scaling ground motions. The results show that the fundamental period could meet basically the requirement of low-rise buildings, in addition, 0.2T₁~2T₁ is adequate for medium- and high-rise buildings.