Abstract: The Da-Xiong Palace in Si-Chuan province is taken as an example to study the damage of ancient buildings by Wenchuan earthquake.Typical damage characters of the structure are discussed and a finite element model is built.By modal analysis basic frequency and main modes of structure are obtained.By dynamic analysis responses of displacement and stress of the structure are obtained.Resultsshow that the main reason for incline of columns of the structure is that tenon pulled from mortise of some tenon-moritse joints between tie beams and columns,but the structure will not be destroyed for strength failure under seismic forces.