NOVELTY - An alkaline anion exchange membrane is prepared by dissolving imidazole compound in toluene or benzene, heating, condensing and refluxing, reacting, and distilling to obtain poly-imidazole compound; dissolving poly-imidazole compound using absolute ethyl alcohol, stirring and condensation refluxing, reacting, and distilling to obtain the solid matter-imidazole onium salt; film casting imidazole solution; and blending film of polybenzimidazole, polyimide, polyether-ether-ketone, polyether sulfone mixed emulsion on the paved glass plate, and heating; and obtaining pale yellow film, and drying.    USE - Alkaline anion exchange membrane for alkaline fuel cell system (claimed).    ADVANTAGE - The membrane has high conductivity, good flexibility, good thermal stability and electrochemical stability.    DETAILED DESCRIPTION - An alkaline anion exchange membrane is prepared by:    (A) dissolving imidazole compound of formula (I) in toluene or benzene; after dissolving, the concentration is 2-10 mol/L, under the action of the free radical initiator, heating at 50-80 degrees C, magnetic force stirring, condensing and refluxing and introducing the protective agent, reacting for 3-12 hours, and distilling to remove solvent to obtain poly-imidazole compound;    (B) dissolving poly-imidazole compound using absolute ethyl alcohol, where the concentration is controlled at 10-50 mass%, adding 1-6C halogenated hydrocarbon, where the mol ratio of the substance is 2:1 to 1:4, at 65-120 degrees C, magnetic force stirring and condensation refluxing under the protection of nitrogen, reacting for 10-30 hours to make it quaternized on 3-N, distilling to remove solvent to obtain the solid matter-imidazole onium salt;    (C) adding the solid material in the water, where the concentration is 1-10 g/L, raising to 50-90 degrees C, magnetic force stirring, swelling, dissolving in polar organic solvent(s), and controlling the total mass concentration at 2-20%, mixing the two solutions, blending under heating to 40-80 degrees C to form an emulsion, magnetic force stirring to mix uniformly, where the mass ratio of imidazole onium salt to the polybenzimidazole, polyimide, polyether-ether-ketone, or polyether sulfone is 1:4-4:1; and    (D) blending film of polybenzimidazole, polyimide, polyether-ether-ketone, polyether sulfone mixed emulsion on the paved glass plate at 60-90 degrees C for 1-5 hours, and heating at 100-120 degrees C to dry, and then heating up to 130 degrees C for 2-8 hours; and obtaining pale yellow film for cleaning with clean water and ethanol, and drying.    R=1-10C chain or annular mono-olefins, preferably ethylene, propylene, 1-butylenes, 2-butylenes, isobutene, 1-cyclopentenyl or 1-cyclohexenyl.