A semiconductor nanomaterial was prepared and its degradation efficiency on zearalenone (ZEN) was investigated. The photocatalytic material, graphitic carbon nitride (g-C3N4), was synthesized by the conventional thermal cracking method, and its structure was analyzed by (X-ray diffraction) XRD, Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The photocatalytic degradation experiments showed that g-C3N4 induced photocatalytic effects under ultraviolet light (254 nm, including 185 nm), releasing reactive oxygen radicals to degrade ZEN. The experimental conditions for the photocatalytic degradation of ZEN were explored. The results showed that the degradation rate of ZEN was 96.0% when the mass of the photocatalytic material , the wavelength of the UV lamp, the initial concentration and the irradiation time were 20 mg, 254 nm (50 W), 0.5 μg/mL and 60 min, respectively. Meanwhile, the experimental conditions for the photocatalytic degradation of ZEN powder samples were optimized. The results showed that the degradation rate of ZEN was 80.0% when the mass of the photocatalytic material, the wavelength of the UV lamp, and the irradiation time were 800 mg, 254 nm (50 W) and 50 min, respectively. The results could provide a theoretical reference and practical basis for the photocatalytic degradation of ZEN.