A novel hierarchical three dimensional (3D) NiO–CdS heteroarchitecture was successfully synthesized by a facile single pot hydrothermal route and characterized by powder X-ray diffractogram, UV-Vis spectroscopy, BET, FE-SEM and TEM. FE-SEM and TEM analyses revealed the formation of the hierarchical 3D structure of the as-prepared NiO–CdS. The purity and crystalline phase of the individual component in 3D NiO–CdS were determined by a powder X-ray diffractogram. The hierarchical 3D NiO–CdS exhibited enhanced photocatalytic activity for hydrogen generation by water reduction with an AQY value of 6%. In 3D NiO–CdS, the high hydrogen production rate in comparison to 1D CdS NWs (AQY 2%) is mainly attributed to the enhanced specific surface area and facile charge transfer from the conduction band of highly crystalline CdS to the conduction band of NiO, which reduces the recombination rate of reductive electrons and oxidative holes for efficient hydrogen production.