In order to provide an arrangement for pressure compensation for optical devices, particularly spectrometers or the like optical devices, for compensating pressure differences caused by changes in temperature and air pressure between the internal pressure and the external pressure at a housing of an optical device enclosing optical units, which arrangement prevents a contamination of optical functional surfaces of the optical units of the optical device and ensures a constant pressure balance between the interior space and the external surroundings of the housing of an optical device with its optical units while economizing on manufacturing costs, it is proposed that the arrangement for pressure compensation comprises at least one pressure compensating element which is constructed on both sides so as to be permeable to air and which is arranged in a housing opening of the housing wall of the optical device enclosing the optical units.