Abstract: Interference fittings of TiAl turbine shaft and K418 alloy sleeve were studied by the software of finite element method ABAQUS. The variation of stresses in assembling process were simulated and calculated by different fit tolerances, geometry and contact lengths. The danger situation of the shaft and sleeve was found by analyzing the stress distribution, and the measures were put forward to decrease contact stress and improve performance life. By comparison of stress distribution results of the different fit tolerances and different contact length, it was shown that fit tolerance had a main effect on the contact stress, and fit tolerance of 0.15 mm was the optimal choose. And the contact lengths had some effect on the contact stress too. Simulated results at different transitional arc radius showed that it affected contact stress heavily, and it was concerned maximum contact stress in