The invention discloses dual anti-counterfeiting fluorescent ink as well as a preparation method and an application thereof. The method comprises the following steps: reacting citric acid hexahydrate,ethylenediamine, ytterbium chloride hexahydrate, erbium chloride hexahydrate and water to obtain doped carbon quantum dots; mixing rare earth doped carbon dots, dialdehyde nano fibril cellulose, 2-methylpyridine-N-borane and a sodium acetate-glacial acetic acid buffer solution for reaction to obtain a Yb / Er-carbon dot-nano cellulose composite material; and mixing the Yb / Er-carbon dot-nanocellulose composite material, polyvinyl alcohol, methylene blue, sodium stearate, urea and water to obtain the dual anti-counterfeiting fluorescent ink. The method is green, environmentally friendly, low in toxicity and simple and convenient in synthesis method, blue fluorescence and green fluorescence can be emitted, compared with traditional fluorescent ink, the added nano-fibril cellulose greatly improves the rheological property and thixotropic property of the water-based ink, has certain competitive advantages compared with products of the same type, and can be used for important information security anti-counterfeiting application.