The invention provides a preparation method for a normal-temperature-cured polytetrafluoroethylene-modified high-solid-content automobile varnish. The preparation method is characterized by comprising a step of mixing main paint, a curing agent and a diluent according to a mass ratio of 100: 50: (10-15), wherein the main paint is prepared by mixing 40 to 59 parts of mixing monomer, 1 to 5 parts of an initiator and 40 to 60 parts of a mixed solvent under stirring in the presence of nitrogen and then adding 3 to 5 parts of modified transparent oily polytetrafluoroethylene resin drop by drop; the curing agent is prepared by mixing 50 to 60 parts of polyisocyanate, 30 to 40 parts of butyl acetate and 10 to 20 parts of propylene glycol methyl ether acetate; and the diluent is prepared by mixing 50 to 60 parts of butyl acetate with 40 to 50 parts of propylene glycol methyl ether acetate. According to the invention, the liquid polytetrafluoroethylene resin prepared on the basis of independent research and development is added into hydroxyl-acrylic resin, so the prepared automobile varnish has the excellent properties of super self-cleanness, high hardness, super smoothness, weatherability, etc.