We successfully synthesized mesocrystalline Ta2O5 nanosheets supported bimetallic Pd-Pt nanoparticles by the photo-reduction method. The as-prepared mesocrystalline Ta2O5 nanosheets in this work showed amazing visible-light absorption, mainly because of the formation of oxygen vacancy defects. And the as-prepared bimetallic Pd-Pt/mesocrystalline Ta2O5 nanaosheets also showed highly enhanced UV-Vis light absorption and highly improved photocatalytic activity for hydrogen production in comparison to that of commercial Ta2O5, mesocrystalline Ta2O5 nanosheets, Pd/mesocrystalline Ta2O5 nanosheets and Pt/mesocrystalline Ta2O5 nanosheets. The highest photocatalytic hydrogen production rate of Pd Pt/mesocrystalline Ta2O5 nanaosheets was 21529.52 g(-1) h(-1), which was about 21.2 times of commercial Ta2O5, and the apparent quantum efficiency of Pd Pt/mesocrystalline Ta2O5 nanaosheets for hydrogen production was about 16.5% at 254 nm. The highly enhanced photocatalytic activity was mainly because of the significant roles of Pd Pt nanoparticles for accelerating the charge separation and transport upon illumination. The as-prepared Pd-Pt/mesocrystalline Ta2O5 nanaosheets in this work could serve as an efficient photocatalyst for green energy production. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.