This research paper examines the importance of international criminal law in the fight against war crimes and crimes against humanity. Given the contemporary problem of systemic human rights breaches, the paper seeks to analyze the effectiveness, challenges, and evolution of international legal tools used to prosecute the most atrocious violations. It opens with the explanation of what war crimes and crimes against humanity are in terms of international law to proceed to a deeper discussion. The historical approach is used to present the roots and development of international criminal law since the end of World War II to the formation and mechanisms of operation of the International Criminal Court . It presents an analytical view of the most critical international treaties and agreements used for the prosecution of the crimes and examines the respective outcomes. The paper involves several distinct cases to examine their outcomes and evolve certain common and separate conclusions. Research encompasses the major problems experienced by international criminal law, such as jurisdictional, political, and attacking state principles. Today’s advancement and technological development feature the challenges and benefits to investigating and prosecuting war crimes. In conclusion, the paper provides a few recommendations on how to strengthen international human rights focuses on the international alliances and the growing federal subsidiary systems. The research contributes to the nature and importance of the role of international criminal law in human rights enforcement and justice against the severest crimes.