Effect of substrate conditions, including material type, thickness and radius of substrate, on residual thermal stresses of plasma spraying Sm2Zr2O7 TBCs was analyzed though finite element method in this paper. The radial and shear stresses of Sm2Zr2O7 decrease with increasing of distance from the center to edge along radius of specimen, and they decrease abruptly at the edge of the specimen, while the axial residal stress increase abruptly at the edge of substrate. All residual stresses increase with increasing of thermal expansion coefficient of substrate. The thickness of substrate has slight effect on the radial residual stress, and axial residual stress and shear stress are almost uneffected by thickness of substrate. The optimum thickness of substrate is 10mm. Radius of substrate have no effect on radial stress when it is greater than 28mm, and radius of substrate has no effect on axial stress and shear stress of Sm2Zr2O7 TBCs.