Photocatalytic hydrogen generation from water splitting offers a viable potential solution for utilizing solar energy. Here we report a feasible synthesis of flexible bio-inspired Zn0.5Cd0.5S@PAN (polyacrylonitrile) mat shaped photocatalyst with leaf-like structure, which shows high photocatalytic H-2-production activity with a rate of 475 mu mol h(-1) per 50 mg of the photocatalyst and an apparent quantum efficiency of 27.4% at 420 nm. The hierarchically porous structure of the mat-shaped Zn0.5Cd0.5S@PAN greatly enhances the molecular diffusion/transfer kinetics, and enlarges the utilization efficiency of light through the multiple reflections and scattering effect. Moreover, a good dispersion of Zn0.5Cd0.55 nanoparticles (NPs) on the surface of PAN nanofibers prevents their aggregation. These features account for high H-2-production activity of Zn0.5Cd0.5S@PAN. Remarkably, the integrity and flexibility of Zn0.5Cd0.5S@PAN mat-shaped photocatalyst facilitate their separation and re-use after photocatalytic reaction. Hierarchically porous leaf-like mat-shaped photocatalysts with high photocatalytic activity and stability should also find potential applications in solar cells, catalysis, separation and purification processes.