Based　on　the　configuration　and　mechanical　characteristics　of　piezoelectric　actuator,　the　bidirectional　piezoelectric　variable　friction　control　device　which　can　produce　control　force　in　two　orthogonal　directions　was　designed　and　the　relation　equation　of　control　force　with　input　voltage　for　this　control　device　was　presented.　Finally,　one　piezoelectric　variable　friction　control　device　was　manufactured　and　performance　test　of　this　control　device　was　processed.　The　result　of　numerical　analysis　and　experiment　shows　the　bidirectional　piezoelectric　variable　friction　control　device　can　produce　semi-active　control　force　fast,　and　the　performance　of　this　control　device　do　not　change　when　the　frequency　of　input　excitation　varies　and　the　control　force　of　this　control　device　has　stable　mechanical　properties.