Assistant Professor, Faculty of Literature and Humanities, Bu Ali Sina University, Hamedan, Iran
Ph.D. student in international law, Department of public law, Faculty of law and political science, University of Tehran, Iran
The law of war involves rules in order to regulate the strategies and conduct of armed conflicts in a legal order and minimize their harmful effects by humanizing them as much as possible. The mission of this part of the law of war that is responsible for humanizing conflicts is international humanitarian law. International Criminal Law is a branch of public international law in which international crimes and the jurisdiction of international criminal courts to prosecute for the perpetrators of these crimes are studied. International humanitarian law and international criminal law, as two very important branches of international public law that interdependently, at the same time, they have gone through a period of history and various developments; the main purpose of this research is to survey the comparative study of the formal and substantive rules of international humanitarian law and international criminal law in the development and evolution of both legal systems. The method of the present research is descriptive-analytical in a library manner in order to survey the comparative study; in both legal systems. The results of this research showed that these two very important branches of public international law in the procedural and substantive rules have many similarities and differences for the development and evolution of each other.