Wood,　a　widely　used　eco-friendly　material　in　ancient　architecture,　has　endured　for　thousands　of　years.　However,　environmental　changes　over　time　cause　varying　degrees　of　internal　damage,　degrading　mechanical　properties　and　compromising　overall　building　safety.　Investigating　wood＇s　mechanical　properties　and　damage　mechanisms　in　ancient　structures　is　crucial.　This　study　simulates　real　conditions　of　ancient　wooden　structures　by　subjecting　three　common　fresh　woods　(beech,　maple,　sylvestris　pine)　to　extreme　environments:　high-temperature　treatments　(100,　150,　200,　and　250　°C　for　15,　30,　45　min),　water　immersion,　and　exposure　to　acidic/alkaline　environments.　Using　the　MTS　instrument,　longitudinal　compression　and　bending　tests　are　conducted,　analyzing　compressive　strength　and　flexural　performance.　DIC　tracks　both　test　processes,　and　SEM　provides　a　microscopic　analysis　of　damage　mechanisms.　Results　show　that　beech　and　maple　outperform　sylvestris　pine　under　high　temperatures　and　acidic/alkaline　conditions.　In　extreme　environments,　wood＇s　mechanical　strength　correlates　with　moisture　content　and　hemicellulose　decomposition.　High　temperatures　enhance　wood＇s　mechanical　properties　through　dehydration　reactions,　but　prolonged　exposure　leads　to　continuous　hemicellulose,　cellulose,　and　lignin　decomposition,　ultimately　reducing　wood＇s　mechanical　performance.　©　2024