The article is devoted to one of the most complicated and peculiar problems of modern psychiatry — the presumption of mental health. Its originality is seen in the fact that practically all speaking and writing about it noted the importance of this principle for the protection of rights and legal interests of citizens, failing into the field of psychiatry. However, expressing this opinion, doctors and lawyers offer very few arguments in support of this view. Traditional arguments in favor of the presumption of mental health, scattered and unsystematic, prove to be absolutely insolvent. It was also found out that the similarity of the presumption of mental health with the presumption of innocence is capable to entail negative consequences. The noted similarity strengthens stigmatizing effect of psychiatric diagnosis, making it extremely undesirable for the patient, and the basis of the relationship between the patient and the doctor laid counterproductive antagonistic model as the model of mutual relations of the accused with the prosecutor. The main conclusion of authors is that the supporters of the presumption of mental health have yet to prove its right to exist, to work out its content and try to neutralize some of the negative consequences of its possible implementation in practice. Without compliance with the listed conditions to bring the presumption of mental health to the level of one of the fundamental principles of Russian psychiatry would be premature.