Abstract: Based on the preliminary research results of earthquake disaster risk assessment in the Guangdong-Hong Kong-Macao Greater Bay Area, the earthquake environment, distribution of disaster-bearing bodies and site characteristics of urban agglomerations in the bay area are analyzed, and two scenario earthquake principles for determining the earthquake input are proposed, namely, setting earthquakes in potential source areas principle and maximum risk setting seismic principle, which can make risk assessment of earthquake disasters in urban agglomerations more accurate. On the basis of previous studies, the expression of earthquake disaster risk considering the influence of site conditions is proposed. The disaster risk assessment method of buildings and lifeline engineering suitable for 3D simulation of seismic input within non-uniform excitation is explored, and the idea of considering the influence of site in the disaster risk assessment of buildings and lifeline engineering is proposed. Some valuable suggestions are put forward to objectively evaluate the earthquake disaster and loss risk of urban agglomeration.