This article discusses the theoretical foundations of editing synonymous units in translation on the basis of translation studies, lexical-semantic analysis and the principles of stylistic editing. The relevance of the research lies in the fact that synonymous units in the process of translation function not merely as words with similar meanings, but also as important linguistic means that convey the stylistic tone of the text, its communicative purpose, pragmatic effect and national-cultural content. The article analyzes the role of synonymy in the language system, the semantic differentiation of synonymic series, denotative and connotative layers of meaning, the degree of stylistic neutrality and expressiveness, the criteria for selecting equivalents in translation, as well as the issues of ensuring semantic accuracy and stylistic appropriateness in the editing process. In addition, the article examines such cases as semantic shifts, stylistic inconsistency, excessive repetition, narrowing or broadening of meaning that may arise as a result of the inappropriate use of synonymous units in a translated text. The study evaluates the editing of synonymous units as an important stage in ensuring the adequacy, naturalness, accuracy and communicative effectiveness of the translated text. The results of the article are of theoretical and practical significance for scientific research in the fields of translation theory, practical translation, text editing, lexicology and linguostylistics.