This paper discusses the bearing mechanism of ancient wooden structure from the aspects of damage and degradation of material, column foot, gaps and performance of mortise-tenon joints, performances of Dou-gong and wooden frame. A time-varying model of the wood component was proposed based on the macroscopic and microscopic analysis of the wood properties. Then the mechanical model and the fine analysis method of the wooden column with rocking-uplift behavior were established. Also, the probability distribution model of gaps of mortise-tenon joint was established, the model and analysis method of mortise-tenon joints were constructed. And the mechanical properties of single Dou-gong and the synergistic effect of Dou-gong layer were analyzed. Finally, the comprehensive seismic mechanism including the friction energy dissipation of the joints, gravitational potential energy storage of the heavy roof and the energy release of the frame by long period rocking were summarized through the experiment and theoretical analysis of the rocking wooden frame, which can provide reference for the further research and protection of the traditional wooden frame.