NOVELTY - All-solid-state polymer electrolyte comprises ester of polyethylene glycol methyl ether methacrylate monomer, polydimethylsiloxane, an inorganic oxide polymerized composite and doped organic lithium salt. The organic lithium salt is lithium trifluoromethanesulfonate, lithium bis(oxalato)borate or lithium bis(fluorosulfonyl)imide. The inorganic oxide is silicon oxide or titanium oxide.    USE - The electrolyte is useful for solid-state lithium-ion battery (claimed).    ADVANTAGE - The electrolyte has good electrical conductivity, and good battery performance.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing the electrolyte, comprising (i) dissolving inorganic acid alkyl ester in an organic solvent A, to obtain solution A, and adding water-soluble organic solvent B, to obtain solution B, controlling the pH at 3-4.5, adding solution B dropwise into solution A, and subjecting the solution to hydrolysis reaction at 50-70 degrees C for 1-3 hours, to obtain an inorganic sol particle, adding a coupling agent, under the protection of atmospheric conditions, and then reacting at 70-90 degrees C for 1-3 hours, to obtain sol particle reaction liquid, and adding organic solvent A and organic solvent B, to obtain a water-immiscible organic solvent, where the inorganic acid alkyl ester is of formula (R1(OR2)4) (I); (ii) adding polyoxyethylene methyl methacrylate monomer, polydimethylsiloxane and an initiator into the step (i) product, reacting at 70-90 degrees C for 4-6 hours, to obtain amorphous poly(ethylene glycol)methyl ether methacrylate (PEGMEM)-co-poly(dimethylsiloxane) (PDMS)-inorganic oxide nano-composite reaction liquid, where the total concentration of polyoxyethylene monomer methyl methacrylate and polydimethylsiloxane, is 0.2-1 g/ml, and the cncentration of initiator is (3-5)x 10-4 g/ml; (iii) adding the step (ii) product into a reaction container at 140-160 degrees C for 10-15 hours, and separating, and drying under vacuum conditions, to obtain PEGMEM-co-PDMS inorganic oxide nano-crystals; and (iv) dissolving step (iii) product in organic lithium salt using an organic solvent C, stirring for 20-24 hours, to obtain highly dispersed nano-particle suspension, casting suspension by film deposition, taking out organic solvent C, and carrying out vacuum drying, to obtain the final product.    R1 = Ti or Si; and    R2 = C atoms having 1-5 alkyl groups.