The invention provides a supramolecular intercalated structure light stabilizer and a preparation method thereof. An ultraviolet absorber and a radical scavenger are innovatively commonly assembled into LDHs interlayer, the ultraviolet absorption property of the ultraviolet absorber is used to block the photodegradation of plastics by ultraviolet rays, and the radical scavenger is sued to captureactive radicals generated by the photodegradation in order to reduce the photooxidation of the plastics. The ultraviolet absorber at the LDHs interlayer and the radical scavenger have synergistic anti-light and anti-ageing effects, and the anti-light and anti-ageing performances of ultraviolet absorber and radical scavenger co-intercalated LDHs are obviously better than those of ultraviolet absorber single-intercalated LDHs, so the disadvantage of poor anti-light and anti-ageing effects of the existing ultraviolet absorber single-intercalated LDHs is overcome. The preparation method has the advantages of simplicity, abundant sources of raw materials, and convenience in industrial production. The prepared supramolecular intercalated structure light stabilizer has the advantages of high heatresistance, good migration resistance, excellent light protection performance and the like, and can be widely applied to the fields of plastics and coatings.