Hydrogen production from solar energy has emerged as a crucial method for hydrogen energy. Herein, a novel NH2-MIL-101(Fe)/Zn0.5Cd0.5S (FMZCS) heterojunction photocatalyst with a hierarchical structure is successfully fabricated via hydrothermal technique. Under simulated sunlight, FMZCS composite containing 3 wt% of Fe-MOF shows superior photocatalytic capability in pure water with a hydrogen generation rate of 954 μmol/h, surpassing that of pure ZCS and Fe-MOF, and demonstrating remarkable photocatalytic stability over four cycles. The exceptional photocatalytic capability of FMZCS is primarily owing to the construction of type II heterojunction. This accelerates the detachment of photo-induced charge and suppresses photogenerated charge recombination. The current investigation presents a novel photocatalytic material for photocatalytic water decomposition.