Abstract
The great Wenchuan earthquake caused tremendous losses of life and property. Building collapse reasons are analyzed in view of structural earthquake resistance. It is pointed out that building collapse is the wrestling result between advantage ousfactors and disadvantage ousfactors. The severity of the great Wenchuan earthquake may result from large magnitude, strong ground motion, wide spread surfacerupture, densely populated people, large numbers of houses, road sand bridges, lower level of seismic fortification, as well as serious geological disasters.