Being a configuration of logically interconnected statements realized in moves and stages, an argumentative essay is built around the notion of textual unity achieved through lexico-grammar and semantic associations. The study attempted to analyze the role of cohesion in the rhetorical structure of undergraduate EFL students. Hence, the 13 moves in the three-stage argument structure were analyzed on a preset framework of cohesion analysis. Discourse analysis as a research method was used to ascertain how cohesion functioned in the rhetorical structure of these argumentative essays. The results revealed the presence of cohesive associations between the different moves of the rhetorical structure which corresponded with the move length. Referential and Lexical cohesion had a more frequent and dense presence than the co-referential element in the sample texts; however, the relatively low incidence of conjunctives pointed towards the relative scarcity of rhetorical functions in students' writing. The study proposes a research initiative that could use frameworks other than the present study or compare two or more sub-genres for the use of cohesion in the rhetorical structure.