The solid-phase photocatalytic degradation of polyvinyl chloride (PVC) plastic with AgNbO₃/Fe₂O₃ is studied under visible-light irradiation. The PVC-(AgNbO₃/Fe₂O₃) samples are characterized by X-ray photoelectron spectroscope (XPS), scanning electron microscope (SEM), gas chromatography (GC), and UV-vis diffusion reflectance spectra (UV-vis DRS). The photocatalytic properties of PVC-(AgNbO₃/Fe₂O₃) samples are systematically investigated. More amounts of generated CO₂, greater texture change and higher weight loss rate were exhibited in the system of PVC-(AgNbO₃/Fe₂O₃) than pure PVC film. The weight loss rate is ten times higher than that of pure PVC film, which reaches to 46.53% with optimum amount of 0.5 wt% Fe₂O₃. Active radicals generate primarily on the surface of Fe₂O₃ particles, which cause composite plastic decomposition on the PVC-(AgNbO₃/Fe₂O₃) interface and extend into polymer interor. The study provides a new promising way to degrade the plastic waste under visible-light.