NOVELTY - A raw material mixture comprising alkoxysilane (II) and alkoxysilane (I) and catalyst composition comprising water, acidic catalyst and organic solvent are mixed. The alkoxy groups of alkoxysilanes (I) and (II) are hydrolyzed. An active energy ray is irradiated. The resulting reaction composition is coated on a base material (10) and active energy ray is irradiated. The radical polymer obtained by radically polymerizing hydrolyzate of alkoxysilane (I), and hydrolyzate of the alkoxysilane (II) are condensed. An inorganic compound film (20) is formed on gas-barrier resin layer (30).    USE - Manufacture of gas-barrier film used for packaging material. Uses include but are not limited to foodstuffs, pharmaceuticals, solar cell module, liquid crystal display panel, and organic electroluminescent display panel.    ADVANTAGE - The method enables manufacture of gas-barrier film having excellent gas-barrier property to oxygen and water vapor even at high temperatures, and reduced crack formation even when external force by deformation of bending and thermal expansion is applied.    DETAILED DESCRIPTION - A raw material mixture comprising an alkoxysilane of formula (II) and an alkoxysilane of formula (I) in mass ratio of 0.25-4 and a catalyst composition comprising 100 pts. wt. water, 0.001-5 pts. wt. acidic catalyst and an organic solvent are mixed such that the number-of-moles of water with respect to total of 1 mol alkoxysilane (I) and alkoxysilane (II) is 0.5-100 mol. The alkoxy group of the alkoxysilane (I) and the alkoxy group of the alkoxysilane (II) are hydrolyzed, to obtain a reaction composition comprising hydrolyzate of the alkoxysilane (I) and hydrolyzate of the alkoxysilane (II). An active energy ray is irradiated to the reaction composition. The hydrolyzate of alkoxysilane (I) is radically polymerized until the polymerization ratio of the R1 group of hydrolyzate of alkoxysilane (I) is 3-50%. The resulting reaction composition is coated on a base material. An active energy ray is further irradiated on the reaction composition such that the polymerization ratio of the R1 group of hydrolyzate of the alkoxysilane (I) is 80% or more. The hydrolyzate of the alkoxysilane (I) is radically polymerized, to obtain a radical polymer. The radical polymer and hydrolyzate of the alkoxysilane (II) are condensed by hydrating, to form a gas-barrier resin layer. An inorganic compound film is formed on the gas-barrier resin layer.    R1=4-9C (meth)acryloxyalkyl or vinyl;    R2,R5=1-8C alkoxy;    R3=1-4C alkyl;    n=0 or 1;    R4=1-8C alkyl;and    m=0-2.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the gas-barrier film.    Synthetic resin film as base material (10)    Inorganic compound film (20)    Gas-barrier resin layer (30)