In　order　to　overcome　the　security　defect　of　the　existing　threshold　signature　scheme,　a　threshold　signature　scheme　withstanding　the　conspiracy　attack　is　proposed.　Analysis　shows　that　this　scheme　can　not　only　resist　conspiracy　attacks　essentially,　but　also　provide　anonymity　and　traceability　simultaneously.　In　addition,　a　conspiracy　attack　is　designed　in　this　paper,　which　is　adopted　to　test　the　current　schemes　and　the　scheme　presented.　The　result　shows　that　current　schemes　can　not　ensure　the　signature　security,　however,　the　proposed　scheme　can　cope　with　this　attack　effectively.