NOVELTY - Crosslinked polymer anion membrane comprising chlorine-containing methyl group polymer film as main chain, is claimed. The crosslinked polymer anion membrane is obtained by ionizing chlorine-containing polymer film of methyl groups with guanidine or biguanide structure crosslinked hydrogel to obtain anion-exchange membrane, where chlorine-containing methyl group polymer film includes ether sulfone, polysulfone, polyphenylene ether or polystyrene, and degree of polymer is 0.1-2 mmol/g-1.    USE - Used as crosslinked polymer anion membrane.    ADVANTAGE - The crosslinked polymer anion membrane has high water absorption film, high swelling rate, and improves the stability of the film base.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparation of crosslinked polymer anion membrane comprising (i) dissolving the chlorine-containing methyl group polymer in a solvent A, adding anhydrous tin(IV) chloride as catalyst and chloromethyl methyl ether as chloromethylation reagent under inert gas protection, reacting at 50 degrees C for 6-48 hours, poring the reaction mixture into methanol or ethanol, precipitating, and drying to obtain chloromethylated product, where solvent A is chloroform, toluene or dichloromethane, and molar ratio between chlorine-containing methyl group polymer, solvent A and chloromethyl methyl ether is 1:200-240:9-10, (ii) carrying out ionization of chloromethylated main chain and ionizing agent at 55 degrees C for 4-24 hours, where ionizing agent is imidazole reagent or biguanide ionizing agent, (iii) dissolving tetramethylurea in a solvent B under inert conditions, and then adding oxalyl chloride, reacting at 60 degrees C for 1-12 hours, removing the solvent B to obtain white powdery solid i.e. guanidine salt, where solvent B is dichloromethane, toluene or diethyl ether, and volume ratio between tetramethylurea, oxalyl chloride and solvent B is 1:1-10:1-1.2, (iv) dissolving guanidine salt in a solvent C, adding triethylamine and diamine, refluxing at 90 degrees C for 12-36 hours, stirring in alkaline solution, separating and extracting the organic phase, evaporating under reduced pressure to remove extracting agent and solvent C to obtain ionizing agent biguanide viscous structure, where molar ratio between guanidine salt, solvent C, diamine and triethylamine is 1:10:2:0-0.5, then dissolving biguanide ionizing agent in solvent C, and then adding binary halide, reacting at 60-120 degrees C for 20 hours to obtain poly-guanidine structure ionizing agent, where molar ratio between biguanide ionizing agent, binary halide and solvent C is 1:10:2, and the solvent C used is acetonitrile, dichloromethane, chloroform or toluene, (v) dissolving guanidine or biguanide structure ionizing agent in solvent D, adding chloromethyl-trimethoxysilane, reacting at 60-120 degrees C for 24 hours, evaporating under reduced pressure to remove solvent D to obtain guanidine or biguanide hydrogel structure, where molar ratio between ionizing agent, solvent D and chloromethyl-trimethoxysilane is 1:5:0.1-2.0, and solvent D is N,N-dimethylformamide, dimethylsulfoxide, N,N-dimethylacetamide or N-methylpyrrolidone, (vi) dissolving hydrogel in solvent D, mixing ionization polysulfone main chain, and carrying out heat treatment in presence of guanidine base catalysis to achieve gel, and placing the resulting solution on a glass plate casting, allowing to stand at 80-120 degrees C for more than 12 hours, and (vii) peeling off obtained film from the glass plate, immersing into 1.0 M aqueous sodium hydroxide solution for 24-48 hours, and drying to obtain crosslinked anion membrane.