A novel Sr2CuInO3 S oxysulfide p-type semiconductor photocatalyst has been prepared by solid state reaction method and it exhibits intriguing visible light absorption properties with a bandgap of 2.3 eV. The p-type semiconductor character of the synthesized Sr2CuInO3 S was confirmed by Hall efficient measurement and Mott-Schottky plot analysis. First-principles density functional theory calculations(DFT) and electrochemical measurements were performed to elucidate the electronic structure and the energy band locations. It was found that the as-synthesized Sr2CuInO3 S photocatalyst has appreciate conduction and valence band positions for hydrogen and oxygen evolution, respectively. Photocatalytic hydrogen production experiments under a visible light irradiation(λ>420 nm) were carried out by loading different metal and metal-like cocatalysts on Sr2CuInO3 S and Rh was found to be the best one among the tested ones. A novel Sr2CuInO3 S oxysulfide p-type semiconductor photocatalyst has been prepared by a solid state reaction method and its exhibits intriguing visible light absorption properties with a band gap of 2.3 eV. The p-type semiconductor character of the synthesized Sr2CuInO3 S was confirmed by Hall efficient measurement and Mott-Schottky plot analysis. First-principles density functional theory calculations (DFT) and electrochemical measurements were performed to elucidate the electronic structure and the energy band locations. It was found that the as-synthesized Sr2CuInO3 S photocatalyst has appreciate conduction and valence band Photocatalytic hydrogen production experiments under a visible light irradiation (λ> 420 nm) were carried out by loading different metals and metal-like cocatalysts on Sr2CuInO3 S and Rh was found to be the best one among the tested ones.