Thermal　barrier　coatings　(TBCs)　are　critical　thermal　protection　systems　for　the　high-temperature　components　of　aero-engines,　and　their　performance　evaluation　is　essential.　Terahertz　nondestructive　testing　(THz-NDT)　technology,　known　for　its　unique　advantages　of　non-contact　application　and　high　penetration　capability,　has　demonstrated　significant　potential　in　evaluating　TBCs.　This　paper　presents　an　overview　of　recent　advances　in　THz-NDT　applications　for　TBCs,　with　a　focus　on　detecting　optical　parameters,　thickness,　porosity,　and　thermal　growth　oxide　of　the　coatings.　Terahertz　time-domain　spectroscopy　enables　an　in-depth　analysis　of　the　physical　properties　of　TBCs　through　two　detection　methods:　transmission　and　reflection.　Moreover,　advancements　in　signal　processing　algorithms,　image　processing　technologies,　and　machine　learning　have　substantially　enhanced　the　sensitivity,　spatial　resolution,　and　real-time　performance　of　THz-NDT.　The　integration　of　these　technologies　has　improved　the　analysis　of　complex　coating　structures　and　broadened　the　application　range　of　terahertz　technology.　However,　terahertz　technology　still　encounters　various　challenges　in　practical　applications,　including　signal　attenuation　in　high-temperature　environments　and　processing　difficulties　due　to　complex　coating　structures.　In　the　future,　as　terahertz　technology　continues　to　advance　and　new　algorithms　are　integrated,　THz-NDT　is　expected　to　play　an　increasingly　vital　role　in　the　quality　assessment,　life　prediction,　and　health　monitoring　of　high-temperature　materials.