The dissertation is devoted to a comprehensive literary analysis of Ukrainian treatises from the late 16th to the 18th centuries within the context of Baroque discourse. Its urgency is justified by following factors: the need to fill the voids in the history of Ukrainian writing and to undertake a deeper exploration of some genres, among which there are treatises that contain value guidance to save faith and spirituality; an urgent need for a more detailed study of their axiology and the rethinking of basic concepts for their understanding and application in today’s reality. The scientific novelty of the results is the treatise for the first time became a holistic object of literary analysis as an original phenomenon of the Baroque era in Ukrainian medieval studies, and also the peculiarities of the existence of treatises in Ukrainian Baroque writing were systematically studied, new approaches to their analysis were used not only from the essential, content positions, but also from the aesthetic and poetics, which contributes to the reception of the worldview of their authors. It has been analyzed the main factors and sources of formation of genre, pointed out main periods of its active function to clarify the genre-stylistic features of treatises in the context of Baroque discourse. The proposed periodization is based not only on the chronological, but also on the aesthetic factor.