Hierarchical TiO2 nanostructure arrays have been successfully synthesized on FTO glass by a facile one-pot hydrothermal method. The novel nanostructure arrays are composed of nanowire trunks and epitaxial nanobranches, and covered by interconnected nanosheets. The UV sensing performance is investigated by integrated them into a photoelectrochemical cell. Benefited from the efficient transport networks and large interface area provided by the novel nanostructure array, the assembled UV sensor exhibits a high responsivity of 0.11 A/W, a fast response time of 20-40 ms for current signal, as well as the self-powered, visible-blind characteristic and considerable spectral response under weak irradiation. Our work has provided an efficient strategy to improve the sensing performance of photoelectrochemical UV sensors by building hierarchical chain-like nanostructures with simple method. (C) 2017 Elsevier B.V. All rights reserved.