Based on the first set of horizontal–component digital seismograms recorded by the 14 stations of Guangdong Digital Seismograph Network, the attenuation of seismic ground motions in the Guangdong region, as well as the site response of each station, were investigated. Various models of geometrical spreading function for the region were examined, and the tri–linear piecewise continuous model was found to give the best results or the least residual errors in the inversion regression. The frequency–dependent Q value of the Guangdong region was found to be Q(f) = 481.5 · f0.31, which was comparable to the Q value of Central Europe. The site responses did not show significant amplifications at these stations located on rock. Based on the ground motion data provided by the Hong Kong Observatory, it appeared that the proposed S–wave attenuation model for the Guangdong region was also applicable for the Hong Kong region.