NOVELTY - A proton conductive film consists of a continuous material of silicon-oxygen cross-linked structure microparticles (1), and pore (2) which penetrates a film, is formed between the microparticles. The proton conductive film has ion exchange capacity of 0.5 meq/g or more, and methanol permeability coefficient of 500 micronsol/cm/day or less measured at 25degreesC using pure methanol.    USE - For fuel cell such as conjugation direct methanol fuel cell and direct methanol fuel cell (all claimed) used as portable power supply for moving component such as vehicle.    ADVANTAGE - The proton conductive film has excellent proton conductivity, methanol-proof property and low methanol permeability.    DETAILED DESCRIPTION - A proton conductive film consists of a continuous material of silicon-oxygen cross-linked structure microparticles, and a pore which penetrates a film, is formed between the microparticles. The proton conductive film has ion exchange capacity of 0.5 meq/g or more, and methanol permeability coefficient of 500 micronsol/cm/day or less measured at 25degreesC using pure methanol. The proton conductive film is used for direct methanol fuel cell, which uses a liquid fuel containing a polar organic solvent.    INDEPENDENT CLAIMS are included for the following:    (1) manufacture of proton conductive film. A liquid mixture containing a compound having mercapto group, covalent bonded hydrolysable silyl group subjected to condensation reaction, and/or silanol group is prepared. The liquid mixture is formed into a film containing a continuous material of silicon-oxygen cross-linked structure microparticles. The hydrolysable silyl group and/or silanol group is subjected to condensing hydrolysis and condensation. A cross-linking agent having hydrolysable silyl group and/or silanol group, water and a catalyst are impregnated into the film, in liquid or gaseous state, and subjected to after-baking. The continuous material of silicon-oxygen cross-linked structure microparticles is oxidized, and sulfonic acid group is introduced into the surface of microparticles. Thus, a proton conductive film is manufactured; and    (2) fuel cell, which has the proton conductive film.    DESCRIPTION OF DRAWING(S) - The figure shows the model of proton conductive film.    silicon-oxygen cross-linked structure microparticles (1)    pore (2)