In the field of mental health, prevention is always the principle, to prevent the occurrence of disease, one of the problems that can be considered in the field of mental and physical health is the issue of war and its examples that lead to violence, for Prevention of war and violence, which has a direct relationship with health (mental and physical), we must pay special attention to the concept of peace and to promote the health of the society, and health at the global and international level. Non-governmental organizations, in turn, in the international and global arena, can be very effective on these two processes (peace/mental health). The expansion of the concept of peace and the development of its process on the one hand and the quantitative and qualitative diversity of non-governmental organizations on the other hand have included many examples of the interaction of non-governmental organizations in the field of peace. In other words, non-governmental organizations have directly and indirectly influenced the peace process, and of course, any type of influence has faced obstacles and challenges. Despite the importance of all the activities of non-governmental organizations in this field, it is not possible to review all of them in this article. Therefore, based on the different stages of the peace process, thematic and content relatedness of the discussions and the qualitative aspects of the effectiveness of non-governmental organizations, three main topics have been chosen. It is necessary to explain that in many cases, it is not easy to accurately distinguish the stages of the peace process. Therefore, it is difficult to distinguish between the effectiveness of the activity of a non-governmental organization in ending a conflict and the role of the same organization in consolidating peace. However, an attempt has been made to explore the effects and obstacles of non-governmental organizations and their role in mental health at the international level within the framework of the usual definitions that have been presented at each stage of the peace process. In this way, the role of peace with mental health and the role of non-governmental organizations in establishing it, and the effectiveness of non-governmental organizations in conflict resolution and arms control and the obstacles facing it are examined. Then, we will examine conflict management and peacekeeping in the second stage of the peace process, and analyze the role of non-governmental organizations and the challenges ahead. Finally, we will discuss the consolidation of peace and the presence of non-governmental organizations in judicial authorities.