To solve the problem of the origin of the human language,it is proposed to use the principle of“ontogeny recapitulates phylogeny”under the assumption that the development of the child’s language to a certain extent reflects the development of the human language.Taking as a basis the first sounds pronounced by a child,phonostems are determined and used when comparing etymological complexes for several semantic fields on lexical materials of several European and Asian languages.According to the results of the comparison,the effectiveness of the used principle has been estimated.