The present invention provides a gas-permeable membrane comprising a partial structure represented by formula (I) or formula (II), (wherein R1 and R2 each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkenyloxy group having 2 to 6 carbon atoms, an aryl group or an aryloxy group, M1, M2 and M3 each independently represents a metal atom, m1 represents an integer, n1, n2 and n3 each independently represents an integer of 1 to 3, * represents a bonding hand), a composition for forming the gas-permeable membrane and a production process of the gas-permeable membrane.