The transformational generative grammar theory is one of the linguistic theories that caused fundamental changes in linguistics since 1950s. This theory is based on the themes: deep structure and surface structure. Chomsky, who introduced the transformational generative grammar, explained the language with processes in mind in 1950s by including mind processes into linguistics. He clarifies the concept of deep structure in mind processes. He aims to emphasize the thought aspect in language by deep structure. This research intends to reveal that the theory of Chomsky depending on the mind processes and explained as the thought aspect in language: deep structure indeed dates back before the 1950s. Within this context, Nahiv as one of the works of Fıtrat is analysed. As a linguist Fıtrat displays the deep structure by establishing a relationship between the mind and language and drives the semantics forward. This research indicates the similarities between the deep structures of Fıtrat (in Nahiv) and Chomsky. This research is done by means of document analysis method as one of the qualitative research methods. Content analysis method that is one of the data analysis methods is used. Similarities between the deep structures of Fıtrat’s and Chomsky’s are identified. As a result of the study, it is proved that the deep structure which constitutes the fundamentals of transformational generative grammar theory is introduced before the 1950s and this work of Fıtrat has already been designed in the transformational generative grammar system.