Coupling between the electronic and crystallographic defect structures of anodic ZrO 2 films has been explored using the recently developed photoelectrochemical impedance technique. With this technique, the dynamic photocurrent response for ultra-violet excitation was analyzed. Additionally, photo-stimulated capacitance transients were also examined. Our studies indicate that, upon UV irradiation, photo-generated holes are transported to the oxide/solution interface by a diffusion/migration mechanism. Coincidentally with this electronic response, oxygen ion vacancies also migrate through anodic zirconia films upon UV irradiation. This leads to photo-stimulated formation of ZrO 2 . The rate-limiting step in this film formation process is the transport of oxygen ion vacancies in the film by a diffusion/migration mechanism. Both the photo-electric response and the photo-ionic response of anodic zirconia films can be explained by the point defect model for anodic films.