The article deals with zero values in natural languages. It at the same time emphasizes that the given factor applies to other semiotic systems as well. The author thinks that the zero value is a universal category when it concerns natural languages and that it can be established at all linguistic levels. Сonsideration is further given to zero values in morphonology and phonology. Тhe author finds that morphonological oppositions can be explained in the domain of phonological distinctive factors and that the zero morphonological value represents the only one difficulty in this respect. The zero value, however, exists in the phonological sphere as well, which is in some languages marked by means of spelling, but without a material, phonetic ground, for example in French. In this way the possibility for linguistic description is simplified and the question of morphonology as a linguistic category is thus shown in another light.