Considering the difference of 3 dimension interface topography unit, the distribution of residual stress in thermal barrier coating was calculated using ABAQUS soft by finite element method. The calculating result shows that the residual stress is affected by interface topography unit obviously. Compressive stress exists in concave topography unit and tensile stress in convex topography unit. Stress concentrates in boundary of topography unit and reaches maximal value at the lowest and the highest place of concave and convex topography respectively. Compressive and tensile stress change with the size of topography unit distinctly.