Background: although the search for biomarkers of mental disorders that is aimed at improving diagnosis, individualizing therapy based on knowledge of pathophysiological processes and preventing the development of mental illness is actively underway for endogenous mental disorders, the study of biological markers in non-endogenous mental disorders and post-traumatic stress disorder (PTSD) in particular has received much less attention. Aim: to analyze current state of research dedicated to genetic and biochemical biomarkers that can be used to identify high risk groups and clarify the diagnosis of PTSD. Material and method: keywords “biomarkers”, “post-traumatic stress disorder”, “pathogenesis” have been used to find in PubMed articles published in 2010–2020. Conclusion: research methods for elucidating the mechanisms of PTSD are actively developing, however, the identification of specific biomarkers (biochemical, molecular, genetic, epigenetic, neuroimaging, psychophysiological) is a complicated task. This complexity is associated with numerous pathogenic mechanisms of PTSD and frequent comorbidity with mental disorders (depression, anxiety) and somatic diseases, as well as lack of specificity of detected biomarkers.