In the context of linguistic interest in institutional discourse, the definition of the core classification features is paramount, as it is a necessary component of the linguistic analysis of a particular subject area. The relevance of considering the institutional discourse typology is due to the fact that although well-known classifications do not include economic discourse, the terms economic discourse (ED) and business discourse (BD) are often used in parallel in Russian philological research, leading to a confusion of concepts and inaccurate analysis of linguistic material. The aim of the study is to confirm (or refute) the hypothesis of ED and BD dissimilarity in the course of a comparative analysis. The novelty of this study lies in specifying the list of institutional discourses. For the first time, an attempt has been made to substantiate the distinction between ED and BD. As a result of theoretical analysis of Russian and foreign notable works on this subject, as well as integrated use of functional-pragmatic, linguistic-cognitive and contextual research methods of economic and business texts, 12 typological characteristics of ED and BD have been identified and considered. Their comparative analysis shows partial similarities as well as distinctive differences between ED and BD in most parameters, including genres, the chronotope, the status-role model, the way discourses are constructed and their underlying mental models. The conclusion made about dissimilarity of DD and ED can have both theoretical and practical significance in examining and mastering the specificity of communicative behavior in relevant social contexts and situations.