Lanthanum　zirconate　is　a　promising　candidate　material　for　thermal　barrier　coating　(TBC)　applications　due　to　its　low　thermal　conductivity　and　high　temperature　phase　stability.　However,　its　application　is　limited　by　thermal　durability　caused　by　low　fracture　toughness　and　low　coefficient　of　thermal　expansion.　We　recently　developed　LZ/8YSZ　composite　TBC　systems　using　blended　LZ　and　8YSZ　powders,　which　have　demonstrated　excellent　thermal　cycling　performance.　In　this　study,　the　mechanical　properties　of　the　composite　TBCs　were　characterised　using　both　nanoindentation　and　Vicker＇s　microhardness　tests.　The　nanoindentation　results　show　that　both　Young＇s　modulus　and　nanohardness　increase　with　increasing　8YSZ　content,　suggesting　the　mechanical　properties　can　be　tailored　by　changing　the　volume　ratio　of　8YSZ.　The　ratios　of　Young＇s　modulus　to　nanohardness　remain　constant,　similar　to　18,　irrespective　to　the　coating＇s　composition.　The　microhardness　results　show　the　same　dependence　with　8YSZ　content,　which　is　confirmed　by　the　analytic　models　based　on　composite　theory.