Pd modified ZnIn2S4/P25 (Pd@ZnIn2S4/P25) heterostructures have been synthesized by hydrothermal and photo-reduction method. The H2 evolution rate of optimal photocatalyst 0.5 %Pd modified 5ZnIn2S4/2P25 (0.5 %Pd@5ZnIn2S4/2P25) are approximately 9100 and 3693 μmol · g−1h−1 under simulated sunlight and visible light irradiation with ethanol as the sacrificial agent, which are nearly 9 and 460 times higher than pure ZnIn2S4 and P25, respectively. The promoted photocatalytic performance can be attributed to the physicochemical properties of the catalysts and the strong electronic interaction between Pd modified ZnIn2S4 (Pd@ZnIn2S4) and P25, the improved transfer rate of photo-generated electrons and holes, the inhibited recombination of charge carriers, and the enhanced light harvesting. The results of photo-electrochemistry and EPR indicate that it is a Z-scheme photocatalytic system, in which the electrons accumulate on the conduct band of ZnIn2S4 and the holes assemble on the valence band of P25. This work provides an effective method to construct highly efficient photocatalytic systems for solar H2 generation.