Nanostructured zinc oxide overlayered by nanoporous strontium titanate was synthesized using sol-gel method and tested in a photoelectrochemical (PEC) cell for splitting of water. It was found that compared to the pristine ZnO and SrTiO3, the resistivity of bilayered thin film was reduced and a negative shift in open circuit potential and flatband potential of bilayered ZnO/SrTiO3 was observed, thus improving the photocurrent density and photoconversion efficiency. Significantly, bilayered ZnO/SrTiO3 thin film offered the best photocurrent density i.e. 0.46 mA/cm2 at 0 V/SCE. XRD, SEM and UV-Vis spectroscopic studies were carried out to explore the structural, surface morphological and optical properties of various thin films.