Epidemiology can be considered as a responsible public health science the aim of which is to control health problems. One of the most important public health problems is “war”. The aim of the present paper, therefore, is threefold: firstly, to determine to what extent war has been investigated from an epidemiological point of view; secondly, what the definition and scope of “war epidemiology” would be; and thirdly, if it would be possible to introduce a new branch of epidemiology entitled “peace epidemiology”. In the present study, I have tried to fulfill the aims of the study based on my experiences in war and peace epidemiology and also by reviewing the most relevant websites, documents and papers. Evidence suggests that enough epidemiological studies have not been carried out to determine the sheer public health consequences of war. “War epidemiology” can be defined as “the study of the distribution and determinants of war-related events in specified populations, and the application of this study to the control of war”. “Peace epidemiology” is a new branch of epidemiology which “highlights how peace could positively shape our world”. Epidemiologists need to produce more scientific evidence about the negative public health consequences of wars and also the positive public health consequences of peace. The ultimate aim of “war epidemiology” is to control war, usually by secondary and tertiary prevention activities. However, the ultimate aim of “peace epidemiology” is to reinforce peace by primary and/or primordial prevention activities.