A　tubular　variable　friction　damper　with　variable　stiffness　characteristics　was　presented　herein.　The　damper　was　composed　of　a　sleeve　cylinder　and　a　inner　friction　ring.　The　inside　diameter　of　the　sleeve　cylinder　was　slightly　smaller　than　the　outer　one　of　the　inner　friction　ring.　When　the　friction　ring　was　inserted　into　the　sleeve　and　moved　back　and　forth,　the　assembly　stress　arised.　The　variable　friction　function　was　realized　through　cutting　slots　along　the　axial　direction.　Due　to　breaking　the　wall　in　the　middle　part　of　the　sleeve　cycle　where　the　inner　ring　was　initially　placed,　thus　the　constrained　stress　between　the　sleeve　cylinder　and　the　friction　ring　was　approximately　zero　in　initial　state　of　the　damper.　When　the　friction　ring　moved　around,　the　friction　damping　force　generated　accordingly.　The　results　showed　that　a　structure　equipped　with　the　variable　friction　damper　has　the　characteristics　of　half-active　variable　stiffness,　i.e.,　when　the　structure　departs　away　from　the　equilibrium　position,　the　damper　provides　greater　friction　force　with　increase　in　relative　displacement　between　the　sleeve　cylinder　and　the　inner　ring;　in　the　other　hand,　when　the　structure　comes　back　to　the　equilibrium　position,　the　damper　provides　gradually　less　friction　force.　The　performance　test　and　finite　element　simulation　for　the　damper　showed　that　the　damper　can　achieve　the　anti-vibration　performance　of　the　active　variable　stiffness　control　needing　supports　from　computer　and　servo　feedback　device.　The　proposed　damper　had　advantages　of　simple　structure　and　large　output　force,　it　met　the　requirements　of　vibration　reduction　for　various　structures　and　machineries　and　it　was　applicable　in　engineering.