The invention provides a polyvinyl chloride lampshade with high light transmittance and a preparation method thereof. The lampshade comprises the following components in parts by weight: 100-120 parts of polyvinyl chloride, 10-13 parts of talcum powder, 10-13 parts of fumed silica, 1-2 parts of aluminum sulfate, 2-3 parts of sodium fluosilicate, 4-5 parts of polyurethane, 1-2 parts of polyether glycol, 4-5 parts of epoxy stearate, 0.3-0.5 part of lauryl dimethyl amine oxide, 0.1-0.2 part of zinc pyrithione, 0.4-1 part of diphenylmidazoline and 1-3 parts of polyamide wax micro powder. The lampshade provided by the invention is resistant to high temperature and poaching, and is high in light transmittance; most light emitted by a lamp can penetrate through the lampshade, so that a use ratio of electric energy is improved, a significant progression is achieved in the field of production of energy-saving and environment-friendly materials, and the lampshade is of great and practical significance.