Dimension　errors　in　root　part　of　a　turbine　blade,　which　are　formed　in　manufactural　process　or　by　wearing　out　during　service　leads　to　contact　conditions　between　the　blade　root　and　disc　groove　changed.　As　a　result,　a　shift　of　fundamental　frequencies　of　the　blade　and　redistribution　of　stress　in　the　root　will　occur,　which　possibly　causes　failure　of　the　blade.　Influence　of　the　dimension　errors　on　contact　status　between　the　blade　root　and　the　disc　groove　and　on　fundamental　frequencies　of　the　blade　is　investigated　by　three　dimensional　finite　element　analyses.　A　finite　element　model　of　a　blade　with　fir　shape　root　and　its　matched　disc　groove　is　constructed　and　then　analyzed　by　taking　account　of　large　deformation　of　the　blade　and　contact　nonlinear　in　the　root.　The　results　show　that　locations　of　the　errors　have　significant　influence　on　fundamental　frequencies　especially　for　bending　modes　of　the　blade.　Magnitude　of　the　error　has　almost　no　influence　on　frequencies　but　affects　contact　status　and　thus　affects　the　stress　field　in　the　root.　The　results　also　suggest　that　considering　the　contact　between　blade　root　and　disc　groove　is　necessary　to　obtain　more　real　fundamental　frequencies　of　a　blade-disc　component.