In this study, the photocatalytic properties of AgBr/Ag3BiO3 (AB/ABO) composite prepared using co-precipitation method followed by ion exchange on the degradation of Rhodamine B (RhB) cationic dye and methyl blue (MB) anionic dye using visible-light was examined. The structural, morphological and optical characterization of the nanocomposite obtained was investigated by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and UV–Vis diffuse reflectance spectroscopy (DRS) analysis. The X-ray photoelectron spectroscopy (XPS) was used to investigate the surface chemical composition and states. The exceptional removal of RhB and MB dies (96% and 100 % for RhB and MB, respectively, at 80 min of degradation) was mainly attributed to the heterojunction creation with excellent surface properties that enhance the efficiency of photogenerated charge separation. A possible photocatalytic mechanism, based on DRS and XPS results, was proposed and related to the efficient charge separation of photogenerated electron–hole pairs. This provided interesting insights into the design and fabrication of Ag-based photocatalysts.