NOVELTY - Microporous film enhanced multi-layer fluorine-containing crosslinked doped ion film comprises 2-40 layers of films formed by fluorine-containing ion exchange resin. Thickness of ion film is 10-300 mu . A film layer is provided with a cross linked net structure. Inorganic dopant is added to a film layer having water holding function or proton-exchange function. The fluorine-containing ion exchange resin is formed by copolymerizing fluorine-containing olefin with one or multiple fluorine-containing alkene monomers.    USE - Microporous film enhanced multi-layer fluorine-containing crosslinked doped ion film for use in fuel cell production.    ADVANTAGE - The microporous film enhanced multi-layer fluorine-containing crosslinked doped ion film improves mechanical strength of ion film, increases stability of film and has high ion exchange capacity and electric conductivity.    DETAILED DESCRIPTION - The microporous film enhanced multi-layer fluorine-containing crosslinked doped ion film comprises 2-40 layers of films formed by fluorine-containing ion exchange resin. Thickness of ion film is 10-300 mu . A film layer is provided with a cross linked net structure. Inorganic dopant is added to a film layer having water holding function or proton-exchange function. The fluorine-containing ion exchange resin is formed by copolymerizing fluorine-containing olefin with one or multiple fluorine-containing alkene monomers. The fluorine-containing olefin is selected from tetrafluoroethylene, trifluorochlorethylene, trifluoroethylene, hexafluoropropene or vinylidene fluoride. The fluorine-containing alkene monomer has formula (I, II, III, IV, V or VI).    a, b, c=0-1;    n=0 or 1;    X=F, Cl, Br or I;    d=0-5;    Rf1, Rf2 and Rf3=perfluoroalkyl and chlorofluoroalkyl;    Y1, Y2 and Y3=SO2M, COOR3 and PO(OR4)(OR5);    M=Br, F, Cl, OR or NR1R2;    R=methyl, ethyl and propyl;    R3=H, Na, Li, K, ammonium radical, methyl, ethyl or propyl;    R4 and R5=H, Na, Li, K, ammonium radical, methyl, ethyl or propyl;    Y4 and Y5=Cl, Br, I or CN;    k, l and m=0 or 1;    X1=F, Cl, Br or I;    n=0 or 1; and    Rf4, Rf5 and Rf6=perfluoroalkyl.    An INDEPENDENT CLAIM is included for a method for producing microporous film enhanced multi-layer fluorine-containing crosslinked doped ion film, which involves:    (A) preparing solution or melt containing fluorine-containing ion exchange resin and inorganic dopant;    (B) molding, extruding, heat pressing, spin coating, casting, screen printing and spray painting or dipping the mixture;    (C) preparing multi-layer film by compounding single-layer films;    (D) adding cross linker and/or evocating agent; and    (E) treating film having crosslinked structure.