Cyclic　symmetry　in　bladed　disc　is　often　destroyed　by　difference　in　blade　structural　properties　and　this　results　in　mistuning.　The　effect　of　centrifugal　force　on　the　mistuning　of　bladed　disc　was　investigated　by　three　dimensional　finite　element　analyses.　Vibration　characteristics　of　mistuned　bladed　disc　caused　by　random　Young＇s　moduli　in　all　blades　were　also　investigated　by　probability　method.　The　results　indicate　that　the　centrifugal　force　reduces　the　localization.　As　Young＇s　moduli　of　blades　are　in　the　tolerance　of　5%,　the　bladed　disc　can　be　treated　as　a　cyclic　symmetry　structure.