The performance of metal oxide-based devices for humidity impedimetric sensors depends on different conduction mechanisms during water molecules adsorption. As consequence, new strategies for development of hierarchical and doped structures of mixed metal oxides play a critical role in the production of more efficient humidity sensors. It is reported an alternative method for synthesis of hexagonal ZnO nanocrystals on TiO2-decorated electrospun fibers, allowing the production of ordered arrays of hierarchical TiO2/ZnO nanostructures. Polymeric matrix supporting fibers were removed after annealing (500 A degrees C), providing nanostructures with promising application as low-cost humidity sensors. The structure of resulting materials was explored in addition to the influence of relative humidity (RH) (measured in the range 400 Hz-40 MHz) on complex impedance spectra.