Abstract
Abstract Recently, the language of one of the oldest Turkic written records, which are dated back to VII-IX centuries, the Orhon Old Turkic monuments are studied in different aspects, considering that these inscriptions contain important historical, linguistic and cultural data on Old Turkic period. In addition, the language of Old Turkic inscriptions, as the earliest valuable written data for language reconstruction and establishment of genetic relations of modern Turkic languages, is still a frequent subject in Turkological studies, as well as in Altaic studies. Suffixation is widely used productive word formation in Old Turkic as well as in Modern Turkic languages as an agglutinative type of languages. The study of suffixal morphemes in the language of Old Turkic inscriptions is important in reconstruction of archetypes, etymological base of suffixes and historical development of word formation process of Modern Turkic languages. This paper presents a detailed description of suffixes in Old Turkic inscriptions, giving the morphemic –structural, semantic and etymological analyses and historical development of derivations in modern Turkic languages.