An ion exchange membrane obtained by using an ionic monomer having at least two or more polymerizable functional groups, in which a hydrophobicity index H obtained by an expression below from a monomer for forming an ion exchange resin and a material fixed to the resin in the ion exchange membrane is 1.6 or greater, and a manufacturing method therefor. Hydrophobicity index H=Σ{(log P of each component)×(molar ratio of each material in resin)}.