The synthesis of LiNbO3-type R3C ZnSnO3 is still a challenging task under an extremely high-pressure condition. In this work, we have not only successfully synthesized R3C ZnSnO3 nanowires (NWs) through a hydrothermal process, but ZnSnO3 NWs with a high concentration of oxygen vacancies (referred to as [Formula: see text] NWs), exhibiting a highly efficient hydrogen evolution reaction compared to unannealed ZnSnO3 and ZnO NWs. The x-ray diffraction pattern and Raman spectra both confirm that the as-synthesized ZnSnO3 NWs mainly belong to the R3C space group with a second phase of ZnSn(OH)6. The conversion efficiency of the solar-to-hydrogen [Formula: see text] NWs and the unannealed ZnSnO3 NWs is 4.8% and 1.5%, respectively. The enhancement factor of the [Formula: see text] NWs is up to 320%. The photocurrent of the ZnSnO3 NWs and the [Formula: see text] NW photoelectrodes is even 5.39 and 16.23 times higher than that of the ZnO NWs, demonstrating that the high concentration of oxygen vacancies is regarded as a useful approach to enhance the photoelectrochemical response. To the best of our knowledge, this is the first report to reveal the performance of hydrogen evolution reaction by LiNbO3-type R3C ZnSnO3 NWs, which could offer a promising way of energy harvesting when using ferroelectric materials.