NOVELTY - A mixture of polyethylene oxide and polyvinylidene fluoride-hexafluoropropylene is dissolved in a solvent, nanoparticles are added, heated, and milling process is carried out in a flask with reflow tube under inert gas atmosphere. An inactive supporter is immersed into the obtained gel solution, the supporter is taken out after 10-20 minutes, and naturally dried to obtain supported-nanoparticles-doped gel polymer film. The polymer film is dried under vacuum condition, and immersed into electrolyte solution, to obtain supported-nanoparticles-doped gel polymer electrolyte.    USE - Preparation of supported-nanoparticles-doped gel state polymer electrolyte used for lithium ion battery.    ADVANTAGE - The supported-nanoparticles-doped gel state polymer electrolyte is efficiently and economically manufactured with high productivity in short period of time, and has high ion conductive ratio and mechanical strength.    DETAILED DESCRIPTION - A mixture (0.5-5 mass%) of polyethylene oxide and polyvinylidene fluoride-hexafluoropropylene is dissolved in a solvent, nanoparticles are added, heated at 30-50 degrees C, and milling process is carried out for 2-10 hours in a flask with reflow tube under inert gas atmosphere. An inactive supporter is immersed into the obtained gel solution after dissolving completely, the supporter is taken out after 10-20 minutes, and naturally dried to obtain supported-nanoparticles-doped gel polymer film. The polymer film is dried at 40-55 degrees C for 10-20 hours under vacuum condition and under the environment in which water content is less than 60 ppm and oxygen content is less than 2000 ppm. The dried polymer film is immersed into an electrolyte solution for 1-2 hours, to obtain supported-nanoparticles-doped gel polymer electrolyte. INDEPENDENT CLAIMS are included for the following:    (1) supported-nanoparticles-doped gel state polymer electrolyte for lithium ion battery; and    (2) application of supported-nanoparticles-doped gel state polymer electrolyte in preparation of polymer lithium ion battery.