Optical coherence tomography (OCT) is evaluated as a promising technique for microstructure characterization of plasma sprayed ceramic coatings. OCT combines the principles of low coherence interferometry and optical heterodyne detection to obtain both a high sensitivity to weakly backscattered light and a high axial resolution. It thus can be used to accurately locate interfaces where the refractive index changes abruptly within translucent materials. In the present work, OCT is used to collect B-scan images of thin yttria stabilized zirconia (YSZ) coatings detached from their substrate. The interferograms forming the B-scans are then analyzed individually to successfully gather information related to light penetration depth inside coatings. The interferogram analysis also allows the evaluation of the refractive index of YSZ tetragonal phase. Thereafter, OCT images of plasma sprayed ceramic coatings will be shown and different approaches for establishing correlations between the microstructure and relevant OCT interferogram parameters will be presented.