The invention relates to a method for producing thin porous membranes made of cross-linkable silicone compositions (S), according to which method an emulsion is formed from the silicone compositions (S) using a pore forming agent (P) in the presence of an emulsifier (E) and optionally solvent (L) in a first step, the emulsion is given a form and the solvent (L), if present, is allowed to evaporate in a second step, the emulsion is cross-linked in a third step, and the pore forming agent (P) is removed from the cross-linked membrane in a fourth step. The invention further relates to membranes that can be produced according to the method and to the use thereof for separating mixtures, in adhesive plasters, as a water-repellent and breathable layer in textiles or as packaging materials.