This article tries to review the international legal positions to be met by each state in ensuring the right of a participant in criminal proceedings to use his native language or the language he speaks and providing such a person with an interpreter in order to exercise this right. The international community has developed documents that contain generally recognized legal norms in regulating the application of the right to use their native language by a person who does not speak the language of legal proceedings and with the help of an interpreter free of charge. The developed legal approaches are interconnected and complement each other, while they serve as a certain reference point for bringing national legislation in line with international requirements. The exercise of the right under consideration ensures the protection of the rights of participants in criminal proceedings. Based on the review of international legal acts and decisions of the European Court of Human Rights, the features and problems of exercising the right under consideration in multinational states are identified, proposals are formed to ensure the right of participants in criminal proceedings to use their native language in accordance with international standards. Ensuring the right to use the native language is a guarantee of the rights of participants in criminal proceedings. It ensures high-quality and effective proof in a criminal case, provided that persons who do not speak the state language are provided with a professional interpreter capable of efficiently translating the information.Keywords: the language of legal proceedings, the European court of human rights, guarantees, protection, translation.