Rose-red color Nb2Zr6O17-xNx oxynitride photocatalyst was synthesized by thermal ammonolysis of Nb2Zr6O17 at 1073 K. TEM image of Nb2Zr6O17-xNx sample showed prismatic pseudo orthorhombic shaped particles with clear edges and an average particle size in the range of 80-90 nm. The photocatalytic activities of the oxynitride samples were studied for hydrogen production by H2S splitting under visible light irradiation. The oxynitride Nb2Zr6O17-xNx gave the quantum yield of 13.5% in the production of hydrogen from decomposition of hydrogen sulfide under visible light irradiation. (c) 2007 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.