Photoluminescence (PL) spectra of yttria-stabilized zirconia (YSZ) samples with different Fe mole fractions were measured to study the influence of Fe doping on their spectra. The PL spectra of all the samples can be decomposed into two Gaussian bands centered around 440 and 510 nm, and the two bands can be attributed to oxygen vacancy states in the bulk and the surface of the samples. We found that the intensity ratio of the PL band around 440 nm to that around 510 nm increases as the Fe mole fraction increases. This can be explained by considering the distribution of Fe-associated defects (bulk or surface) and the PL quenching by the defects. These results show that PL spectroscopy can be used to study properties of Fe dopant in YSZ. Moreover, photoacoustic spectra of the samples were measured to characterize defects in the samples. (C) 2006 Elsevier B.V. All rights reserved.