In the history of Armenian architecture, the Ani Cathedral plays a key role and importance, which, with its stylistic originality, innovation of compositional, artistic forms of structures, had a great influence on the entire further course of the development of Armenian architecture. The achievements of the creative Cathedral of Ani are linked with the name of the outstanding architect of medieval Armenia Trdat, who in the course of his fruitful activity created magnificent and unsurpassed monuments. Famous scientist, architect Toros Toramanyan highly appreciated the importance of Trdat in Armenian architecture. The role of Trdat in the formation of the Armenian architectural identity is invaluable. One of the best manifestations of the creative personality of Trdat is the Cathedral of Ani, which plays a significant role in the development of artistic forms of church architecture. The Cathedral, with its splendor and ideological content, was called the power of Armenian statehood.