In this paper, effect of top-layer thickness on thermal-shocking property of plasma-spraying DCL coating of Sm2Zr2O7 and YSZ was studied by FEM. Results show that radial stresses decrease with time increasing, and their maximum values are increase with top-layer thickness increasing. They have similar distributions along horizontal distance which decrease gradually with increasing top-layer thickness. Radial stresses at YSZ layer/ bonding layer remians almost compressive stresses state which is helpful to increase bonding strength the TBCs. Axial stresses remians almost unvariable along horizontal distance in the range from 0mm to 15mm, they change abruptly from negtive stresses state to positive stresses state at edge of TBCs sample. Axial stresses also decrease gradually with increasing top-layer thickness.