The palace-style timber building in Tang Dynasty is the earliest wooden structure remains in China, which has extremely precious historical and scientific research value. In order to further study the horizontal resistance of this kind of timber frame, the refined finite element model of single-room timber frame with four columns verified by model test was established, and the influences of brackets complexes, column head and column foot,load and position of vertical load on the mechanical performances of the timber frame were studied. The results show that the palace-style timber frame in Tang Dynasty swayed and uplifted under the horizontal reversed cyclic load, and its horizontal displacement was mainly the horizontal displacement of column frame layer, and the S-shaped hysteretic curve of the structure is anti-symmetric with pinch effect, which two ends are relatively full. The initial lateral stiffness of timber frame is the largest, and its degradation is obvious with the increase of displacement.The brackets complexes layer is a structural layer with high rigidity, and there is a certain redundancy in the connection between its beams. Both the column head and column foot can enhance the hysteretic energy dissipation and lateral force resistance of the timber frame, but they play different roles in different stages. The larger the vertical load is, the greater the hysteretic energy dissipation and the greater the lateral resistance are. The displacement of the action position within a column diameter length has no obvious effect on the hysteretic energy consumption and lateral force resistance of the timber frame.