In order to reduce the impact of CdS photogenerated electron-hole recombination on its photocatalytic performance, a narrow band gap semiconductor MoS2 and organic macromolecular cucurbit[n]urils(Q[n]) were used to modify CdS. Q[n]/CdS-MoS2 (n=6, 7, 8) composite photocatalysts were synthesized by hydrothermal method. Infrared spectroscopy (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (SEM), ultraviolet-visible (UV-Vis) and photoluminescence spectrum (PL) were used to characterize the structure, morphology and optical properties of the products, and the catalytic degradation of the solutions of methylene blue, rhodamine B and crystal violet by Q[n]/CdS-MoS2 composite catalyst was investigated. The results showed that the Q[n] played a regulatory role on the growth and crystallization of CdS-MoS2 particles, Q[n]/CdS-MoS2 (n=6, 7, 8) formed flower clusters with petal-like leaves, the flower clusters of petal-like leaves increased the surface area and active sites of the catalyst, the Q[n]/CdS-MoS2 barrier width decreased, the electron-hole pair separation efficiency was improved in the Q/Cds-MoS2. Q[n] makes the electron-hole pair to obtain better separation and migration. The Q/CdS-MoS2 and Q/CdS-MoS2 have good photocatalytic activity for methylene blue, and the catalytic process is based on hydroxyl radical principle.