A series of porous MoS2/Fe-g-C3N4 heterojunction composites were fabricated and their photocatalytic performance for hydrogen evolution via water splitting under visible light irradiation were measured. The 3% MoS2/Fe-g-C3N4 showed excellent photocatalytic performance and recyclability, and the rate of hy-drogen production reached to 48.2 μmol•/h which is 5.47 times of pure g-C3N4. The physicochemical properties of materials were also investigated by XRD, FTIR, SEM, TEM and XPS and the optical proper-ties were tested by PL and UV-vis. The results showed that the crystallinity of Fe-g-C3N4 decreased greatly and the Fe doped materials presented a porous structure with larger specific surface area. Furthermore, the MoS2/Fe-g-C3N4 materials showed more visible light absorption and faster electron-hole separation which was mainly because the newly-formed heterojunction.