A method for producing a waveguide in a multilayer substrate involves producing at least one cutout corresponding to a lateral course of the waveguide in a surface of a first layer arrangement comprising one or a plurality of layers. A metallization is produced on surfaces of the cutout. A second layer arrangement comprising one or a plurality of layers is applied on the first layer arrangement. The second layer arrangement comprises, on a surface thereof, a metallization which, after the second layer arrangement has been applied on the first layer arrangement, is arranged above the cutout and together with the metallization on the surfaces of the cutout forms the waveguide.