Abstract: The g-C₃N₄ binary complex was prepared by self-assembly at room temperature, and the flower like g-C₃N₄@ZIF-8@MoS₂ composite photocatalyst was prepared by hydrothermal method. The structure of g-C₃N₄@ZIF-8@MoS₂ composite was characterized by X-ray diffractometer, scanning electron microscope and energy dispersive spectrometer. The photocatalytic performance of g-C₃N₄@ZIF-8@MoS₂ composite was investigated by photocatalytic degradation of methylene blue. The results showed that the g-C₃N₄@ZIF-8@MoS₂ composite had good stability in water, high catalytic efficiency, and good degradation effect on methylene blue (99% degradation in 90 minutes).