The article is devoted to the problem of completed suicides among veterans of the Joint Forces for National Security and Defense operation in Donetsk and Luhansk regions (JFO) and liquidators of the consequences of the Chornobyl accident (LCCA). The results of the analysis of surveys of families and close associates of JFO veterans who committed a completed suicide in the period 2014–2019 are presented. The survey was conducted as part of criminal proceedings initiated on the facts of suicide. Objective: to analyze the current dynamics of suicidal behavior in veterans of JFO and the impact of psychosocial factors on its development and compare with the relevant indicators among LCCA at the Chornobyl nuclear power plant. Materials and methods: 175 questionnaires are presented, socio-demographic characteristics are compiled and psychosocial factors that influenced the development of suicidal behavior in environmental protection veterans are identified. An analysis of the status of such studies among liquidators of the Chornobyl accidents. Results: the data analysis of suicidal behavior in veterans of environmental protection, the impact on its development of psychosocial factors and comparison with the indicators among LCCA at the Chornobyl Nuclear Power Plant. Conclusions: The results of the study show that in emergency situations, mostly men from all regions of the country, both professional servicemen and civilians, are involved in its elimination. It has been proven that while performing their official duties, the veterans of JFO and LCCA at the Chornobyl nuclear power plant experienced mental stress. But most of them, returning home, did not seek medical treatment, prevent the development of diseases and their complications and remained for a long time without proper medical, social and psychological care. Key words: completed suicides, suicidal behavior, psychosocial factors, veterans of environmental protection, liquidators of the Chornobyl accident.