The article is devoted to studying the specifics of the functioning of the future tense as an important component of the Bulgarian temporal system in the era of the Bulgarian Proto-Renaissance. The research object is an 18th century copy of the «Small Catechism» written by Theodore the Studite, which is a part of the manuscript no.1/154 from the Hryhorovych’s collection kept in the Odesa National Scientific Library. The primary method used for researching the history of languages – the comparative-historical method, is employed here. The involvement of the internal reconstruction approach makes it possible to determine the internal regularities of the development of the Bulgarian language that are valid beyond a particular time. The New Bulgarian monuments, dating to the XVII–XVIII century, from the Odesa manuscript collection are yet not sufficiently described and require careful and in-depth research, that proves the expediency of carrying out this analysis. Furthermore, studying the written monuments of the New Bulgarian period helps to supplement the knowledge about the development of the future tense, and the transformation of its forms, some specific stages of which remain undisclosed. The paper analyzes the forms of the future tense recorded in the text (both simple and compound), characterizes their structural, grammatical and functional particularities, and compares them with other manuscripts of the same period. The article pays special attention to the fact that contrary to the general tendency of using the auxiliary verb щетъ and da-constructions or the abbreviated infinitive as components of future tense forms, the main elements of the forms in the studied manuscript are хотэти and infinitive. The use of combinations б©д© + infinitive as a future tense form, which is not typical for the Bulgarian language history, is fixed. The analysis presented here highlights the regular use of simple future tense forms in subordinate clauses and ascertains their sporadic use in principle ones. Additionally, it notes the special impact of the archaic Middle Bulgarian written tradition and Church Slavonic language of the Eastern redaction on the formation of future tense form in the manuscript.