Metalloporphyrins (MPyds, M = Co, Ni, Cu, Zn) bearing three 4-pyridines and one benzoic acid as meso-position substituents are adopted as photosensitizer of Pt-loaded carbon nitride (C3N4) for visible-light-responsive H-2 production, and the photosensitization shows an increasing trend in the sequence of CoPyd < NiPyd < CuPyd < ZnPyd under visible light irradiation. Among various MPyd sensitized C3N4 products (MPyd/C3N4), ZnPyd/C3N4 achieves the best H-2 production activity (524 mu mol h(-1)) with an impressive apparent quantum yield of 32.3% at 420 nm monochromatic light irradiation, higher than that of CoPyd (24.5%), NiPyd (26.1%) and CuPyd (28.3%) sensitized C3N4 products. Further investigations demonstrate that the distinctions in the photosensitization of those MPyds on C3N4 can be ascribed to the different central metal ions, which result in different absorption spectra, electrochemical properties and charge transfer processes. The present study is the first time to explore the effects of central metal ions on the photosensitization of metalloporphyrins over semiconductor for visible-light-responsive H-2 production, and provides a promising approach to highly efficient solar-to-hydrogen conversion through molecular design of metalloporphyrins for utilizing the visible light of sunlight.