We reported the facet controllable synthesis of BiOI nanosheets to expose {001} (BiOI-001) and {100} (BiOI-100) facets by adjusting reaction time of hydrothermal process. Photocatalytic results revealed the facet-dependent photocatalytic property for CO2 reduction on BiOI nanosheets. Photoluminescence (PL), photocurrent, UV-vis diffuse reflectance spectra (DRS), X-ray photoelectron spectroscopy (XPS), valence-band XPS spectra and theoretical calculation results revealed that BiOI-001 have better separation efficiency of photo-induced carriers and higher CB position. These positive factors resulted in the {001}-dependent photocatalytic activity of CO2 conversion on BiOI nanosheets. (C) 2016 Elsevier B.V. All rights reserved.