The invention discloses a preparation method and film-forming liquid for an aluminum alloy high-performance trivalent chromium hybrid conversion film. The film-forming liquid is added with phosphotungstate serving as an inorganic corrosion inhibitor, and amino trimethylene phosphonic acid, hydroxy ethylidene diphosphonic acid and Ethylenediamine tetramethylene phosphonate; and when an aluminum or aluminum alloy workpiece is treated by the film-forming liquid, a trivalent chromium, phosphotungstate and organophosphorus hybrid conversion film can be formed on the surface of an aluminum alloy. Compared with a single trivalent chromium conversion film, the hybrid conversion film can improve the corrosion resistance of the aluminum alloy and achieve the anti-corrosion effect of a hexavalent chromium chemical conversion film.