Aim. To present a methodological system of work on the prevention and correction of errors in written speech of Iranian students studying Russian. Methodology and methods. The analysis of scientific and methodological literature on the research topic was carried out. A comparative analysis of the forms, techniques and methods of teaching Iranian students the Russian language, including such a type of speech activity as writing, is carried out. In addition, the method of pedagogical observation of the educational process and the method of studying the products of students’ activities – generalization and interpretation of linguistic material (written works of Iranian students) have been applied. Results. The classification of typical mistakes made by Iranian students in written essays in Russian is presented. A system of exercises has been developed aimed at a) preventing speech errors, b) correcting (editing and literary editing) mistakes made. Research implications. The scientific novelty of the study lies in the fact that it substantiates the necessity and expediency of creating a methodological system for overcoming errors in writing in Russian by students with native Persian. The essence of the methodology lies in the fact that a special place in the process of developing the speech competence of foreign students is given to learning the lexical compatibility of words. The didactic material consists of words and word combinations with a high degree of use, the vocabulary is organized thematically and structured in a special way. The results of the study can be used by teachers in classroom classes in groups of Iranian students who speak Russian in the volume of the I certification level. Conclusions. In groups of Iranian students, it is necessary to carry out systematic work on the prevention or correction of errors in written texts created in Russian in order to develop language and communicative competence. An effective form of work is the performance of exercises for the assimilation of the norms of lexical compatibility.