Dovetail attachment is a typical structure of turbomachine connecting blades and disk (rootblade and slotdisk contact with each other). Fretting wear and surface fatigue fracture tend to occur under higher thermal and vibration loads in dovetail attachment interface, where blade usually happens to fatal failure. FEA method was applied to solve the complexity of the contact interface stress of dovetail attachment. The contact pressure and contact slide distance of dovetail attachment were calculated under different friction coefficient and different rotational speed. The calculation shows that contact pressure and contact slide distance reduce as friction coefficient increases, and the contact pressure and contact slide distance enlarge as rotational speed increases.