Abstract: In this experiment, a Z-scheme nitrogen-deficient graphite-phase carbon nitride (LaFeO₃/CQDs-g-C₃N_x) composite photocatalyst was prepared. The catalyst was characterized by X-ray diffraction (XRD), ultraviolet-visible diffuse reflection (UV-Vis DRS), photoluminescence spectroscopy (PL), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The results showed that the introduction of nitrogen defects and CQDs enhanced the migration efficiency of photogenerated carriers. The photocatalytic degradation rate of LaFeO₃/CQDs-g-C₃N_x composites for rhodamine B (RhB) was 3.98 times higher than that of pure g-C₃N₄, and had good photocatalytic stability. It also showed good degradation of antibiotics and other organic pollutants.