Double-ceramic-layer (DCL) thermal barrier coatings (TBCs) of La 2 (Zr 0 . 7 Ce 0 . 3 ) 2 O 7 (LZ7C3) and Eu 3 + -doped zirconia, which was partially stabilised by 8wt% yttria (8YSZ:Eu), were prepared by atmospheric plasma spraying. A thermal cycling test was carried out. The 8YSZ:Eu sublayer exposed during thermal cycling could produce visible luminescence under ultraviolet (UV) illumination, providing an indication of the spallation and damage degree of the coating. The result shows that the application of a Eu 3 + -doped luminescence sublayer can be a very simple and useful non-destructive technique to indicate the spallation and damage degree of DCL coatings.