Giorgi Merchule (Georgian: გიორგი მერჩულე) was a 10th-century Georgian monk, calligrapher and writer who authored "The Vita of Grigol Khandzteli", a hagiographic novel dealing with the life of the prominent Georgian churchman St. Grigol Khandzteli (Gregory of Khandzta) (759-861).

Giorgi was a monk at the Georgian Orthodox monastery of Khandzta in Tao in what is now north-east Turkey. "Merchule" is not the surname of the author but rather an epithet loosely translated as "specialist in canon law" or perhaps "theologian" as posited by the Georgian literary scholar Pavle Ingoroqva. Giorgi's wide knowledge of contemporary canon and patristic literature is indeed evidenced by his work.

Merchule's eloquent and imaginative prose is unsurpassed in Georgian hagiography. His work is not a traditionally formal account of the saint’s life, but rather shows a characteristic interest in the surrounding world. Merchule widened the range of patristic Georgian narrative to cover intimate details, rhetorical pleas and historical facts. Yet, the popularity of "The Vita" does not stem from its literary merits alone. Written in the crucial period when the resurgent Bagratid dynasty, in close alliance with the church, mounted a struggle, ultimately successful, for the unification of Georgian lands, the work articulates the idea of all-Georgian unity and autocephaly of the Georgian church. In one of the most-quoted passages of medieval Georgian literature, Merchule advances a definition of Kartli (a core ethnic and political unit that formed a basis for Georgian unification) based upon religious and linguistic considerations: