An optical membrane element for an optical device in lithography, especially EUV (extreme ultraviolet) lithography, includes at least one membrane layer and a frame, which at least partially surrounds the membrane layer and at which at least part of the rim of the membrane layer is mounted. At least one tautening element is provided, which facilitates tautening of the membrane layer and wherein the optical membrane element can be used in a projection exposure system, especially for EUV lithography, such that the membrane layer of the membrane element can be adjustably tautened, such that the membrane layer is flat. A method for manufacturing a corresponding optical membrane element includes generating a tautening element lithographically together with the membrane layer.