Process for producing zeolite separation membrane

A process for producing a zeolite separation membrane having a porous support containing alumina as a main component and, provided on a surface and within pores of the porous support, a zeolite layer, comprising the seed crystal adhering step of adhering USY zeolite crystal as a seed crystal on a surface and within pores of the porous support; the basis material forming step of bringing a reactant liquid containing silicon and aluminum into contact with the porous support and heating the reactant liquid to thereby obtain a zeolite separation membrane basis material; and the basis material separating step of separating the zeolite separation membrane basis material from the reactant liquid to thereby obtain a zeolite separation membrane. By this process for producing a zeolite separation membrane, there can be produced an FAU zeolite separation membrane capable of satisfactory separation of a mixture of organic solvent and water.