The　Wenchuan　earthquake　in　2008　had　caused　serious　damages　of　many　modern　buildings　but　relatively　slight　damages　of　Chinese　ancient　wooden　buildings.　To　find　out　aseismic　mechanism　of　these　ancient　structures,　Taihe　Palace　in　the　Forbidden　City　was　taken　as　example　for　analysis.　Besides　layout,　its　components　such　as　basement,　column,　tenon-mortise　joint,　Tou-Kung　(bracket　sets),　beam　structure,　roof,　wall　and　so　on　were　all　considered　to　discuss　their　effects　to　aseismic　performances　of　the　whole　structure.　Results　show　that　layout　of　Taihe　Palace　is　reasonable,　which　can　avoid　torsion　mode　of　itself;　its　column　roots　are　set　on　stone　bases　by　free-standing　means,　which　can　absorb　part　of　earthquake　energy　by　sliding　motions　of　column　roots;　its　tenon-mortise　joints　and　Tou-Kungs　can　consume　part　of　earthquake　energy　by　frictions　and　compressions　among　their　components;　low　ratio　of　height　against　width　of　its　beam　structure　can　avoid　sliding　as　well　as　overturn　under　earthquakes;　its　thick　roof　may　enhance　stability　of　the　whole　structure;　finally　the　wall　components　can　reduce　deformation　of　wooden　frames　under　earthquakes.