A number of international laws were adopted and enforced in the last two centuries. However, the efficacy of these laws has always been in question. Some jurists never considered international laws as proper law. World War I and World War II also posed questions on the validity and efficacy of international laws. After the establishment of the United Nation a new international law regime started and it was thought that international law has now established itself as a proper law and is able to regulate the relations between nations. A conception was created that the concepts like sovereignty, human rights, law of war are now well followed. However, Russia- Ukraine hostility once again posed questions not only on the law of war but also on the efficiency of international organizations to control wars. The Invasion of Ukraine seems to be a clear example of ineffectiveness of international laws in the present date. Researchers in the present paper have analyzed the efficacy of international laws in recent times with special focus on the Russia- Ukraine war. Law on war, occupation and human rights are the main laws discussed in this paper.